... 3.Grade:4.8 ,6.8,8.8,9.8.... Copper Bolts,Copper Bolt,Brass Bolts.1.What’s the specification of ... chromium are accord with ROHS Standard.Weight Quantity of each plastic bag will be packing as per the Fasteners' size,and ... technology1. We are a professional manufacturer with more than 20 years experiences in screw,bolt,nut,washer,rivet, stud, pin,wrench and so ...