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 screws(C65100,C65500)contain wood screw,machine screw,lag screw,hex cap screw,carriage screw,ect . All material was purchased from ISO certificated source. manufactured according to ANSI,DIN,BS,as well as non-standard. Output:60tons per month