Do you have such worries?
When you choose or buy locks, you always worry about if it’s durable and antioxidant. This problem is related to the use of materials and finish treatment.
From the perspective of durability of materials, the best material should be stainless steel, especially when is used as the surface material. It has very good strength, corrosion resistance. And its color can remain the same after a long use. Even with continues use, it can become lighter. There are many kinds of stainless steel. The main two are ferrite and austenite. The ferrite is magnetic, commonly known as stainless iron. With the service time and bad environment, it gets rusty easily. But austenite stainless steel is not. So you can identify the two with a magnet.
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