washer .Material:carbon steel,stainless steel .Finish:zinc plated .Size:all kinds 1.NameSpring lock ... DIN, JIS, ISO, AS,BS,etc3.Materialcarbon steel,Stainless Steel4.Finishzinc plated(Cr,3+);zinc plated(Cr,6+),Plain,Hot dipped gavanized ... - 3";M3~M806.Supply abiltity1000 tons per month7.CertificateISO9001:2008;8.Packing By carbon, then by pallet;9.Delivery stamping fastener of carbon steel spring ...