... 316;carbon steel; 2.Surface:polished;galvanized; 3.Good Price and Good Quality; Metal stamping part/Fastener:Stainless Steel 304 or 316 ... galvanized(zinc plating);nickel plating;3.Stainless Steel 304 or 316 spring nut;(Size: 1/4",5/16",3/8",1/2".M6 ... M12*8mm,M12*9.1mm,M12*11.9mm,1/4",3/8",5/16",1/2"; We hope to receive drawings ... we will quote you competitive price asap. A2(SS304) and A4(SS316) spring nut