... screw,drywall screw;Type "M","UNC","UNF","BSW"threads for Machine threads.Head typesHexagon head,Mushroom head,Pan head,Countersunk head ... head,Oval head,Hex flange head,Round head,Ball head,Button head...Socket typesPhillip type,Pozi type,Eleven type,hexagonal type ... used in most of places such as drywall,concrete,chipboard,machine,wood...2) Main export market:North America,South America,Eastern ...