Copper Bolts,Brass 1.ISO,ANSI, ... 8,8.8,9.8.... Copper Bolts,Copper Bolt,Brass Bolts.1.What’s the specification of ... Head typesHexagon head,Mushroom head,Pan head,Countersunk head,Bugle head,Oval head,Hex flange head,Round head,Ball head,Button head...Socket typesPhillip type,Pozi type,Eleven type,hexagonal ... higher than other Carbon Steel .2.Fasteners' Head is much thicker than some other manufacturers , ...