Coupling Fasteners,Connecting 1.ISO,ANSI,CE,DIN,BS& non-standard ... is capable 3.Grade:4.8 ,6.8,8.8..... Coupling Fasteners,Connecting Fasteners,Aluminum Fasteners. 1.What’s the specification ... head,Pan head,Countersunk head,Bugle head,Oval head,Hex flange head,Round head,Ball head,Button head...Socket typePhillip type ...