Silicon bronze fasteners are excellent for use in many marine and commercial applications which was made from copper with silicon added for strength.Silicon bronze is known as a high-strength alloy,having a several important factors including high conductivity,excellent corrosion resistant to sea water,gases,sewage and atmospheric conditions. Our silicon bronze wood screw(C65100,C65500) was made to ANSI,DIN,BS,etc. Length: 6mm-150mm Diameter: #4 - #24 Head style:Flat,Oval,Round,hexagon,etc. Packing:polybag and carton Output:60 tons per month. Sending sample free of charge.