... Head typeHexagon head,Mushroom head,Pan head,Countersunk head,Bugle head,Oval head,Hex flange head,Round head,Ball head,Button head ... plated,Nickel plated,Dacroment Plated,chromium plated,Tin plated,Blackphosphating ,anodized ,and Environmental Plated ... .additional process Washer assembly,Heat treatment,Baking hydrogen,Anti- ... high control force from material till products reach in ... head machine screw