The standard size of the work permit card is 85.5X54 mm (also the international standard for cards), and the larger size is 70X100 mm. Now each unit or company can customize the card size according to its own needs and carry it with you.
A work permit indicates a person’s certificate of employment in a certain unit. Including provincial, municipal, county and other government agencies and enterprises and institutions, etc., mainly showing that someone works in a certain unit. It is a symbol of a company's image and certification.
Extended information
While the work permit is used as a credit card application document, it is also used to prove the income status and level. This is obviously acceptable. And it plays a role in getting the highest possible credit limit. However, the income certificate or work permit is still related to the nature of your unit. The value of work certificates from private companies, governments or public institutions is also different.
You can also apply for a credit card by applying for a credit card, but the limit is generally not very high.
The most useful thing is to provide proof of income with an official seal. A work permit from a government institution can be equivalent to an income certificate. Therefore, it is easiest to apply for credit cards from these units, provided your credit record is good.