... brass,copper Finish:Plain,black,zinc plated,nickle,etc Description:Internal teeth serrated lock washers Features:1)Standard:DIN,ISO,ANSI ... copper3)All types and sizes are available,also produce according to customers'drawings and samples4)Finish:Plain,zinc plated,black, ... HDG,etc.5)Packing:Export Packing (Carton/ Pallet).also according to customer`s requirements Internal teeth serrated lock washers