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Ethereum founder Shanghai 2014 group photo

Publish: 2021-05-15 15:50:08
1.

Buterin, the founder of Ethereum, is a Russian

at the end of 2013, vitalik buterin, founder of Ethereum, released the first edition white paper of Ethereum and launched the project. From July 24, 2014, Ethereum has carried out a 42 day pre-sale of Ethereum coins. In early 2016, Ethereum's technology was recognized by the market, and its price began to soar, attracting a large number of people other than developers to enter Ethereum's world. Two of China's three major bitcoin exchanges, huocoin.com and okcoin.com, both officially launched Ethereum on May 31, 2017

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extended materials:

in 2011, butrin began to realize bitcoin under the influence of his father when he was 17 years old in high school. Butrin showed a strong interest in this new thing. In order to better understand this fully distributed currency, butrin began to read bitcoin forum and technical materials. He wrote bitcoin blog articles to earn bitcoin, although his hourly salary was only $2 an hour

when he made 20 BTCs, he took 8.5 to buy a shirt. But he realized at that time that if thousands of people from all over the world join the bitcoin community, an independent financial system can be created, and the application of blockchain is not limited to cryptocurrency, but applicable to all walks of life. Since then, Butlin has been working in this direction

in late 2011, butrin graally became famous in the community. A man from Romania invited him to co-founder bitcoin magazine and serve as the chief writer

2. Vitalik buterin, the founder of Ethereum and the younger brother of the post-90s generation, is known as "V God" in the Jianghu
bitcoin is a digital currency designed by Nakamoto in 2009. The identity of its founder "Nakamoto" has always been a mystery. Rumors about "father of bitcoin" involve from the US National Security Agency to financial experts, and also give bitcoin a mysterious aura. Matcha exchange can find out more about Ethereum bitcoin
3.

There is an essential difference between Ethereum and bitcoin. What is the difference? Bitcoin defines a set of currency system, while Ethereum focuses on building a main chain (which can be understood as a road) to allow a large number of blockchain applications to run on this road

from this point of view, Ethereum's application scenarios are more extensive, which is why we say that Ethereum marks a simple monetary system in the era of blockchain

1.0, and a transformation to other instries and application scenarios in the era of blockchain 2.0

however, there is no perfect thing in the world. Although Ethereum has expanded the application scope of blockchain in all walks of life and improved the speed of transaction processing, it also has some disputes and doubts

first, the solution to the lack of scalability of Ethereum: slicing technology and lightning network

the bottom design of Ethereum, the biggest problem is that Ethereum has only one chain and no side chain, which means that all programs have to run on this chain equally, consuming resources and causing system congestion. Just like last year's very popular Ethereum game "encryption cat", when this game was very popular, it once caused Ethereum network paralysis

to improve the processing capacity, Ethereum proposes two ways: shard and lightning network. Let's introce these two technologies respectively

(1) fragmentation technology

vitalik buterin, founder of Ethereum, believes that the reason why mainstream blockchain networks such as bitcoin process transactions very slowly is that every miner has to process every transaction in the whole network, which is actually very inefficient. The idea of fragmentation technology is: a transaction does not need to be processed by all nodes in the whole network, as long as some nodes (miners) in the network are allowed to process it. Therefore, Ethereum network is divided into many pieces. At the same time, each piece can handle different transactions. In this way, the network performance will be greatly improved

however, the slicing technology is also controversial. As we all know, the important idea of blockchain technology is decentralization. Only when the whole network witnesses (processes) the same transaction can it have the highest authority. The Ethereum slicing technology is similar to the group witness, not all nodes witness together. In this way, it will lose the absolute "decentralization" attribute, and can only achieve the purpose of high performance by sacrificing certain characteristics of decentralization

(2) lightning network

lightning network uses the way of transaction under the chain. What does that mean? It means: when the participants of lightning network transfer money to each other, they do not need to confirm the transaction through the main chain of Ethereum, but create a payment channel between the participants and complete it under the chain

however, lightning network is not separated from the main chain. Before establishing a payment channel, you need to use the assets on the main chain as collateral to generate a balance proof, which indicates that you can transfer the corresponding balance. In the case that both parties of the transaction hold the balance certificate, both parties can make unlimited number of transfers under the chain through the payment channel

only when the off chain transaction is completed and the assets need to be transferred back to the chain, the balance change information of the main chain account will be registered on the Ethereum main chain, and no matter how many transactions occur ring this period, there will be no record on the main chain

another real benefit of lightning network is that it can save the cost of miners for you. At present, when we trade on the main chain of Ethereum, we need to consume gas and pay for miners. Once we move the transaction to the lower chain, we can save this part of the cost

Of course, lightning network is not perfect. When using the lightning network, the assets on the main chain should be used as collateral; And this part of assets as collateral can not be used before the user completes the transaction under the chain. This also determines that lightning trading is only suitable for small transactions

the above is the problem of insufficient scalability of Ethereum, as well as the two main solutions: fragmentation technology and lightning network

Second, there are loopholes in Ethereum's smart contract and the infamous Dao event

Ethereum's smart contract is very powerful, but there are loopholes in any code. The biggest controversy of Ethereum's smart contract lies in the so-called loopholes, that is, security issues. According to relevant research, 34200 (about 3%) of the nearly 1 million smart contracts based on Ethereum contain security vulnerabilities, which will allow hackers to steal eth, freeze assets or delete contracts, such as the infamous Dao incident

(1) what does Dao mean

before introcing the Dao event, let's first introce what Dao is. Dao is the abbreviation of decentralized

autonomous organization, which can be understood as decentralized autonomous organization. From the perspective of Ethereum, Dao is a kind of contract or a combination of contracts on the blockchain, which is used to replace the government's review and complex intermediate proceres, so as to achieve an efficient and decentralized trust system. Therefore, Dao is not a specific organization, that is to say, there can be many Dao, all kinds of Dao

(2) the infamous Dao event

however, when we talk about Dao now, we basically refer to the Dao event, that is, the infamous hacker attack event we just mentioned. As we know, the English word "the" refers to "the Dao event". The Dao event

refers to "the Dao event", because we just said that Dao is not a specific organization, there can be many Dao, all kinds of Dao

in 2016, slock.it, a German company focusing on "smart locks", launched the Dao project on Ethereum in order to realize decentralized physical exchange (such as apartments and ships). Since April 30, 2016, the financing window has been open for 28 days

unexpectedly, this Dao project is very popular. It raised more than US $100 million in just half a month. By the end of the whole financing period, it raised a total of US $150 million. Therefore, it has become the largest crowdfunding project in history. However, it didn't last long. In June, hackers took advantage of the loopholes in the smart contract to successfully transfer more than 3.6 million Ethernet coins and put them into a Dao sub organization, which has the same structure as the Dao. At that time, the price of Ethernet currency fell directly from more than $20 to less than $13

this event shows that there are loopholes in smart contracts, and once the loopholes are exploited by hackers, the consequences will be very serious. This is why many people criticize Ethereum and say that its smart contract is not smart

to solve this problem, many foreign companies begin to provide code audit services in order to solve the vulnerability problem of smart contract. From a technical point of view, some teams are currently testing smart contracts. Most of these teams are led by professors from Harvard, Stanford and Yale, and some of them have obtained investment from leading institutions

in addition to the problems of insufficient expansibility and loopholes in smart contracts, the controversy over Ethereum lies in the POS consensus mechanism it pursues, that is, the proof of equity mechanism. Under the proof of equity mechanism, if anyone holds more money and holds it for a longer time, he will get more "rights" (interests) and have the opportunity to get bookkeeping power, Bookkeeping can also be rewarded. In this way, it is easy to create the oligarchic advantage of "the stronger the stronger"

Another problem is the chaos of ICO. ICO is a common way to raise funds for blockchain projects, which we can understand as pre-sale. The outbreak of ICO projects on Ethereum has caused illegal activities such as fund allocation and money fraud under the banner of ICO, which has caused security risks to social and financial stability

4. With the upgrading of Ethereum to version 2.0 this year, the consensus mechanism will be converted to POS, which will have a huge impact on miners. There are two choices for miners. One is to sell mining equipment and buy eth to adapt to the stacking mechanism of POS; The second is to switch the miner to other networks supporting GPU miner. Nick foster, a representative of kabombacks, a US mining equipment distributor, said most eth miners would choose the latter

after Ethereum is upgraded to version 2.0 POS mechanism, miners may switch mining machines to other networks
as Ethereum is finally ready to start its Ethereum 2.0 upgrade later this year, thus eliminating the long-term delay, the network will start to move towards the proof of rights model

therefore, the network will give up the workload proof consensus algorithm, so that eth miners have little choice. As their equipment will become obsolete, they will be forced to start mining counterfeit coins or re qualify as eth mortgagors. So, what is the current situation of Ethereum mining? With the coming transition, what will happen to the whole instry< At present, Ethereum consensus is based on POW system, which is similar to bitcoin (BTC). As a result, Ethereum's mining process is almost the same, as miners use their computing resources to earn rewards for each block they try to complete< However, there are still major differences between these processes. Although bitcoin mining has relied almost entirely on ASIC (large, loud machines designed specifically for cryptocurrency mining, most of which are concentrated in areas with low electricity prices), Ethereum's pow hash algorithm ethash is designed to support global chip manufacturers (such as NVIDIA and AMD). As Thomas Heller, global business director of cryptocurrency mining pool f2pool, explained in a conversation with cointegraph, GPU is much cheaper and easier to access than ASIC

"as ASIC is a very professional machine, when a new generation of procts is released, it is usually a huge technological leap. As a result, they have a much higher hash rate and are more energy efficient than the previous generation. This means that those manufacturers have spent a lot of money to research and develop it. Their machines are usually very expensive, and GPUs are much cheaper. "

Heller added that those who use GPU miners "have more flexibility to mine." For example, the popular NVIDIA geforce GTX 1080 Ti card can mine more than 15 different currencies, while ASIC units usually support only one currency

nevertheless, Ethereum is not completely immune to ASIC miners - at least in its current state. In April 2018, bitcontinent released antminer E3, an ASIC specially proced for mining Ethereum. Although widely praised for its hash rate of 180 megahashes per second and power consumption of 800 watts, it has received different responses from the Ethereum community. After the ASIC is inserted, a considerable number of GPU rig owners seem to suffer from loss of profits, and some are even forced to switch to other networks

"in the white paper, ETH must have ASIC resistance. I would like to say that the white paper stands for something "is one of the highest comments on the AR / ethermining topic about the topic discussed when antminer E3 was announced. Another reddit user argued that "the $800 only applies to 180mh."“ Split or die of a nation. "

some Ethereum users continue to suggest that bitmain's mining devices can lead to greater concentration, thus increasing the possibility of attack by 51%. Soon, a group of developers put forward "programmed workload proof" or progpow, which is an extension of the current Ethereum algorithm ethash, aiming to make GPU more competitive and promote decentralization

according to a paper published in March by Kristy Leigh Minehan, co-founder of progpow, about 40% of the hash rate of Ethereum is generated by bitmain ASIC. Alejandro de la Torre, the vice president of poolin, is the sixth largest pool of eth. He confirmed to cointegration that "GPU mining is still dominant" in Ethereum network, and added:

"at present, the profit of eth mining is not high, and the management threshold and cost of GPU equipment are higher than ASIC equipment. Compared with ASIC devices, GPU devices are more flexible, and you can use other algorithms to switch to other coins. "

progpow has not been integrated into Ethereum, and it is not clear when it will be finally implemented - in March, Ethereum core developers were debating whether progpow will really benefit the network in nearly two hours, and failed to reach a consensus. It is worth noting that a bitmain representative has previously told cointegraph that the mining hardware giant does not intend to extend the service life of antminer E3 to start operation after October 2020: "as far as we know, mining will end in October or some time after that."

a safe but uncertain future

indeed, Ethereum will stay away from mining in the future. Ethereum 2.0, which is planned to be launched later in 2020, is a major network upgrade on the blockchain, aiming to transfer its current POW consensus algorithm to a virtual POS (known as "block verifier")

more specifically, users are randomly selected considering their wealth in the network or their "interests". In other words, the more coins a POS verifier chooses to put in, the more coins accumulated as a reward

according to vitalik buterin, the co-founder of Ethereum, e to the transition, the network will be more secure and the attack cost will be higher than the network of bitcoin, although the debate about the better consensus algorithm in the encryption community has lasted for many years. However, it is not clear when to start Ethereum 2.0, as many errors and management issues are reported to be delaying the process

another hypothetical benefit of POS system is that it has higher energy efficiency than pow blockchain. According to digiconomist, the cryptocurrency's total annual footprint is 59.31 terawatts per hour, which is comparable to the electricity consumption of Greece as a whole. However, since a report in July 2019 estimated that 74% of the exploitation of bitcoin was done using renewable energy, the environmental impact of bitcoin does not seem to be so serious

what will happen to the actual Ethereum miner? According to the documentation of Casper upgrade as part of Ethereum 2.0 roadmap, the network will initially support a hybrid model including both POW and POS, thus providing some space for block verifiers and GPU / ASIC miners. Jack O & 39, CEO of skale network; "There will definitely be a transition period when two networks are running at the same time," Holleran told cointegration The CEO of scale network (based on Ethereum's blockchain platform) gave a detailed description of this process:

"the transition from eth1 to eth2 takes time of course - it may be years rather than months. The good news about this slow transition is that dapps and defi platforms will be able to roam around based on survivability, security and real-world evidence of adoption. This is a positive impact on the Ethereum ecosystem. "

dig or not

once Ethereum is fully in the POS orbit, miners will have two options. One is to sell the equipment and use the money to accumulate more Eth and start mortgage. The other is the choice for GPU miners, which is simply switching to other ethash networks and mining counterfeit money. Nick foster, a representative of kabombacks, a US mining equipment dealer, told cointegration that most eth miners would choose the latter:

"what I want to say is that most of the miners have not really entered Ethereum or the mining of specific tokens. Yes, there is a certain amount of mineral deposits and holds, but I oppose the view that a large number of Shanzhai coin miners hold their coins at any time. "<

foster then described how he used 3gb GPU units to mine ethash's point-to-point blockchain asset ravencoin (RVN). Once it was unable to mine eth, he said, "this is the reason for mining crows. I immediately sold stability to BTC, and then sold it to US dollars to pay for my rights. I would say that a lot of people are adopting this strategy. "

as foster concludes, he wants eth miners to jump out of the network, and new players - those who don't invest in power infrastructure or drilling rigs - will take a stake in eth. He described the following:

"I can't imagine if I found a five-year lease with $0.04 of electricity and I was mining eth, I decided to sell everything and then continue to pay the rent so that I could hold eth as a share. Substitute. "

Marc fresa, founder of asic.to, a mining firmware company, agreed in a conversation with cointegraph: "if you invest in mining, you won't bet because you have enough room to grow."

one of the main counterfeit coins that may benefit from POW miners leaving Ethereum is Ethereum classic (etc), which is a more conservative version of the blockchain. It is reported that there is no POS related plan. As it also runs on the ethash algorithm, the startup of Ethereum 2.0 may lead to the migration of miners, so its hash rate may have a significant peak

eth's larger pools have similar options. When asked about the company's plans for Ethereum after pow, Heller told cointegraph that after the announcement of Ethereum's POS upgrade, f2pool launched a sister company called story.fish in early 2018. Story.fish has started to provide mortgage services for other POS and delegated POS projects, such as tezos (xtz), Cosmos (atom) and Cardano (ADA), e to numerous handover delays. For prin, e to the transition to POS, it "may temporarily give up supporting eth mining," de la Torre told cointegraph

other top eth pools, namely nanopool, ethermine, pool center, sparkpool and spiderpool, did not respond to requests for comment from cointegraph.
5.

If you forget the stock capital password and transaction password, there is no other way, you can only bring your ID card, shareholder account card and other relevant materials to the securities counter. For specific questions, you can consult the customer manager

stock account refers to the account opened by investors in securities companies for stock trading

opening a stock account is a prerequisite for investors to enter the stock market

precautions for opening stock account

(1) required certificate: ID card. If a legal person's stock account is opened, the original (or ) of the business license and the power of attorney of the legal person shall be issued at the same time

(2) fees include: application form fee and account opening fee

(3) operation process: investors need to fill in the application form and pay the handling fee; Hold relevant certificates, application forms and receipts of account opening fees to the account opening counter and hand them to the counter undertaker; After the undertaker checks the above materials, the applicant takes back the relevant certificates and receipts and gets the stock account card

extended information:

stock account loss reporting and re handling

(1) Shenzhen securities account loss reporting and re handling

1. If an investor loses his securities account card, he / she can report the loss and re handle the new number of securities account at Shenzhen Branch of China Securities Regulatory Commission or its designated securities business office with his / her ID card

2. If the investor loses the securities account and ID card at the same time, he / she should report the loss and go through the replacement proceres with the ID card loss certificate, account book and its issued by the public security organ

3. If the investor entrusts others to report the loss, the agent should present the legal notarization document at the same time

(two) the loss of the securities account in the Shanghai Stock Exchange and the replacement of the

securities business department will apply for the loss of the securities account according to the following proceres:

1, carefully examine the identity card of the investor (for example, if the identity card is lost at the same time, it must provide the certificate of loss of the body certificate issued by the public security police station under the registered residence, and paste the official seal of my recent certificate); p>

2. All securities in the securities account will be frozen

3. After the investor provides a new securities account with the same securities account registration information opened by the agency of Shanghai Securities Central Registration and Clearing Company, the corresponding securities account transfer proceres shall be handled for the investor

(4) after the securities business department has accepted the transfer of investors' accounts and registered their securities subsidiary accounts, it will send the change information to Shanghai Securities Central Registration and Clearing Company for change registration before the closing of the market on that day

5. The securities business department can handle the application for investors to cancel the loss report, but the securities account that has gone through the proceres of securities transfer can not cancel the loss report

6. When the securities business department accepts the loss report of investors' securities accounts, the Shanghai Securities Central Registration and Clearing Company will change all the securities rights and interests in the loss report account to the account of the transferor at one time

6. Mutual promotion of cryptocurrency development
7. It is also called ethnocentrism. It refers to a common tendency of all countries and nationalities, that is, it is easy to regard their own way of life, beliefs, values and norms of conct as the best and superior to others
take the cultural model of our own nation and group as the center and standard to measure and evaluate other cultures, often hostile or suspicious of the cultural model we are not familiar with
its positive functions are as follows:
1. Enhance the concept and unity of our group, and arouse the loyalty and morale of our members
2
3. Promote cultural stability and consistency, and maintain social order
4. Avoid the feeling of anomie and rootlessness
its negative functions are:
1
2. Make the culture rigid and unable to adapt to the changes of the times
3
4. Maintain the status quo of some classes
5. The situation causing social isolation.
8. In philology, Rida said: & quot; If philology is possible, its prerequisite is the deconstruction of logocentrism; So what is logocentrism
logocentrism is another name of Western metaphysics, which is Derrida's general ruling on western philosophy by inheriting Heidegger's ideas. As the name suggests, logocentrism is a structure centered on logos, so we should first understand & quot; Logos & quot;
& quot; Logos & quot; From ancient Greek, for λ In the first volume of the history of Greek philosophy, gersley, a famous historian of philosophy, analyzed in detail the usage of the word "oyos" in philosophy, literature, history and other documents before the fifth century B.C., and summed up ten meanings: (1) anything spoken or written 2) Things mentioned and related to value, such as evaluation and reputation 3) The inner consideration of the soul, such as thought and reasoning 4) Develop from what is said or written to cause, reason or argument 5) And & quot; Empty talk& quot; Excuse & quot; On the contrary, & quot; The real logos & quot; It is the truth of things 6) Scale, propriety 7) Correspondence, proportion 8) General principle or rule, which is a relatively late usage 9) The ability of reason, such as the difference between man and animals, is that man has logos 10) Definition or formula to express the essence of things.
later generations mainly from & quot; Rationality& quot; Truth& quot; Law & quot; Even & quot; Logic & quot; To grasp & quot; Logos & quot; In Heidegger's being and time, this meaning is not groundless, but it is not its original meaning; Logos & quot; Far away from the basis of existentialism, & quot; Logos is experienced as a ready-made thing and interpreted as a ready-made thing; Similarly, the existential shown by logos also has the meaning of being; Therefore, he wants to put & quot; Logos & quot; From & quot; Logic & quot; In his opinion, he thought that "the first is to liberate and restore its original meaning"; Logos & quot; The original meaning is & quot; Talk & quot; Or & quot; Speaking & quot;, Its verb form is legein and its root is 1eg. The basic meaning of 1eg is & quot; Talk & quot Speech is the basic link of human being's Dasein, which forms the whole meaning of Dasein. It links human being's Dasein as a whole in the way of articulation; Heidegger's later period (from the introction to metaphysics in the transitional period) was not satisfied with the analysis of logos as & quot; Talk & quot;, Therefore, it continues to trace its origin, and holds that its original meaning is & quot; Aggregation & quot;, Gathering brings the miscellaneous and mutually exclusive things into the presence. Speech is also a kind of gathering, which makes all things gather into one and show up; Logos & quot; It is not only the omnipresent operation of being, but also the omnipresent operation of language; Aggregation & quot; To explain & quot; Logos & quot; And use & quot; Talk & quot; Explanation & quot; Logos & quot; Although there are differences between existentialism and ontology, they do not change the two core meanings, that is, to refer to & quot; at the same time; Speech & quot The speech of Dasein or being) and & quot; Presence & quot;, In & quot; Logos & quot; Derrida agrees with Heidegger's research that the pursuit of logos is the pursuit of all presence through speech; However, Derrida believes that & quot; Logos & quot; No matter it is in the normal sense & quot; Rationality & quot; Or & quot; Logic & quot; Or Heidegger insisted successively & quot; Talk & quot; And & quot; Aggregation & quot; In all kinds of metaphysical systems, there is always an unchanging presence as the center of its construction system. Derrida has a good summary of this in the opening of structure, symbol and game in the discourse of Human Sciences: there is a desire for center throughout the history of metaphysics, Different centers organize different structures; The history of the whole concept of structure must be regarded as a series of activities in which the center replaces the center, just like a chain of centers. The center obtains different forms and names in a way of successive emergence and mutual coordination. The history of metaphysics, like the whole history of the west, is the history of these metaphors and metonymies, It can be proved that all these names related to the basis, principle or center indicate an unchanging presence -- Eidos [essence], arche [origin], telos [purpose], Energia [energy], ousia [presence], existence [existence], substance [entity], Suiet [subject], Aletheia [Truth], Transcendentalite, conscience, Dieu, homine and so on; The historical manifestations of these presence are as follows: & quot; The presence of things as Eidos facing eyes, as entity / essence / existence, as temporal presence of present or moving point, as self presence of thinking, consciousness and subjectivity, as common presence of self and others; Derrida's philosophy is just a response to these various modes of presence. He re grasps logos from the perspective of signifying activity, that is, Heidegger's interpretation of logos from the perspective of ontology; Presence & quot; Interpretation is examined at the linguistic level (this is mainly influenced by Saussure, later on in detail): the so-called presence means that the signified is separated from the signifier. In the movement of signs, the signifier is originally indivisible, but metaphysics can make the signifier self erase and make the signified appear, and further regard the signified as the unchanging center and the basis of determination, In order to construct metaphysical edifice, Derrida called it & quot; A priori reference & quot According to Derrida, Heidegger's & quot; Logos & quot; Heidegger liberated language from logic, but constrained language in the presence of logos. Therefore, Derrida wanted to liberate language from logos (no matter what kind of logos it is) and classify it as the game's & quot; Words & quot In Derrida's opinion, logocentrism contains two rather contradictory views: first, it is a sound centered concept, namely phonocentrism. In the phenomenon of expressing meaning with symbols, the medium of sound is superior to that of words. Sound is internal and closest to meaning, while words are external, It can only approach meaning through sound circuitously, which is an ideological tradition based on Western phonetic characters. Secondly, in the activity of care, the sound must be hidden and self erased, so that the meaning can be completely and directly present. This is what Derrida called & quot; Metaphysics of presence & quot In this regard, sound centralism is attached to logos centralism, which serves for logos centralism. The only reason for its existence is to let logos lose its superiority when it is present
9. Watch maintenance in summer
the climate is hot and humid in summer. When people sweat in hot weather, the watch may leave green or black marks on the wrist when it encounters sweat. Due to the different pH value in sweat, the degree of clock erosion is also different. Therefore, it is an important issue for watch lovers to take the initiative to maintain their watches
watch maintenance in summer
the reason why the watch turns green with sweat is that the watch factory adopts gold-plated copper-clad plating which is easy and beautiful in color, but if the gold-plated technology is not handled properly, it will cause the watch oxidation. Nowadays, PVD stainless steel plating technique is widely used in gold plating of watches and clocks, so it is rarely found. Therefore, it is recommended to buy stainless steel or K-gold materials. As for the problem of wrist blackening when wearing a watch, it is directly related to poor air quality and st stuck in the watch strap for a long time. In this case, it's best to give it to a professional watch shop for cleaning. You should also pay attention to the cleaning of the watch when you wear it on weekdays.
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