15 copper nails, 1 cobalt drill nail, etc. These hardware copper nail stump sets are mainly made of pure copper and stainless steel, which are, rust-proof and -. The copper nail stump is made of 99% pure copper, which is thicker than other products and has a long service life; the drill bit is made of cobalt-containing high-speed steel, which is to high temperature, wear and deformation.
