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We often encounter some stainless steel screws in our daily lives, and their heads are marked with letters and numbers. Do you know what these letters and numbers represent? Today we will talk about the performance level of stainless steel fasteners.

The representation method for stainless steel fasteners consists of two parts. The first part marks the group of steel; Part 2 Marking Performance Levels

For example, mark: AB-CD

The first part consists of letters and numbers. The letter A represents the category of steel, and the number B represents the chemical composition of the steel. (For stainless steel with a carbon content below 0.03%, L can be marked after the number, such as A4L-80, which is commonly used to indicate 316L.)

The second part of the marking consists of two numbers CD, representing 1/10 of the tensile strength of the fastener