washer spring external teeth serrated lock washers 1.material:carbon steel 2.standard:DIN/GB ... ANSI 3.finishing:zinc/black washer spring external teeth serrated lock washers1.Metail:Carbon steel,stainless steel,35CrMo,35#.etc. ... DIN ,ANSI/ASME,BS,GB,JIS,Non-standard,JB/T.4.Surface:plain,zinc plated,black oxide,hot dip galv ... Europe,South Korea,Southeast washer spring external teeth serrated lock washers