Spring washer for bolts and nuts to prevent returns Made of stainless steel, it has excellent corrosion and heat resistance. [Features] Spring washer for bolts and nuts is a common No. 2. Anti-return effect. Made of stainless steel, it has excellent corrosion and heat resistance. [How to use] (1) Use it as a return washer when tightening with bolts, small screws, and nuts. (2) It has excellent corrosion resistance, so it can be used in damp locations/outdoor applications.