... for Machine threads.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 ... experiences in screw,bolt,nut,washer,rivet, stud, pin,wrench and so on .2. Our company had good reputation ... other.2.Fasteners' Head is much thicker ,it is strong not break down . meanwhile,socket is much deeper,it ...