... screw, ball screw, hex head screwbolt screw, bolts and nuts, self drilling screw, self tapping screw ... bolts Specification:1) Meterials: carbon steel, stainless steel, metal, brass, copper, zinc alloy, cold rolled steel with ... binding, button, truss3) Surface treatment: kinds of plating (Zinc, Nikel, Chrome, Tin, Ag); Painting, Powder, Anodizing, ... screw brass standoff screw with threads blue zinc plated