The most outstanding advantage of polyamide fiber is that it has superior wear resistance than other fibers, followed by its good elasticity, its elastic recovery rate is comparable to wool, and its weight is light, with a specific gravity of 1.14. Among the commercially available synthetic fibers, it is second only to polypropylene (polypropylene fiber, with a specific gravity of less than 1), It is lighter than polyester fiber (with a specific gravity of 1.38), so polyamide fiber can be processed into fine, uniform, soft and smooth silk for weaving beautiful and durable fabrics. In addition, it has the same advantages as polyester fiber, such as corrosion resistance, no fear of moth damage, and no fear of mildew.