... JIS,NFE,USS,SAE BS and so on) of material(A2,A4,A3.....) Surface treatment Zinc ... has a variety of hardware specifications, in line with the principle of customer first,concentrate on working hardware manufacturing,we ... nut, screw and other mechanical parts in kinds of standards, specifications and materials (A2,A4,A3,Brass ... and so on),most of material is imported from South Korea USA and ...