... .Grade:4.8 ,6.8,8.8,9.8.... Copper Bolts,Copper Bolt,Brass Bolts.1.What’s the specification of our ... Products ? MaterialsCarbon steel,Stainless steel,Alloy steel,Copper,Aluminum are available.Carton steel is high quality iron,such ... is less than 300mm .Threads/ ScrowsType "M","UNC","UNF","BSW"thread are available.Head typesHexagon head,Mushroom head,Pan head,Countersunk ...