... & High quality 3.Kinds of Surface Standard Spring Washer wirh different sizesStandard ones or non-standard requirements or drawings from customers1.Material ... , black, dacromet, geomet or others specified by the customers3.Product Standard: DIN125, DIN126, ANSI/ASME B18.22.1, JIS B1256 or ... may be subjected to vibratory loosening of screws or bolts. American Standard Spring Washer wirh different sizes