... first-rate production line, the most professional staff and advanced quality-test equipment for ss washerstainless steel washerstandard ... .Size:M3-M642.Standard:DIN,ISO,GB,IFI and NON-STANDARD3.Finish:PL,ZP,HDG,sheradizing,plain, ... black oxide,Zinc plated(blue,white and yellow)chrome plated,Cr+34.Materialz:Carbon steel, ... according to the clients. stainless steel washer,bolt,nut,screw