External teeth serrated lock washers Material:65Mn spring steel,stainless steel Finish:Plain,ZP,YZP, ... insert lock nuts, cap nuts, slotted nuts, rivet nutWASHERS: flat washers, spring washers, lock washersSCREWS: machine screws, self tapping screws, set screws ... inquiry, please contact me 0086-13375150195, External teeth serrated lock washers