... steel, carbon steel, coppersurface treatment: zinc plated, passivation, dacroblack,size: M6,M8,M10,M12,M14,M16,M18,M20Length: 50-300mmgrade: 3 ... according to requirement Specifications1.material:carbon/stainless steel 2.size:M6-M20 3.Length:50-300mm 4.galvanized,QPQ,Passivate 5 ...