... ;Type "M","UNC","UNF","BSW"threads for Machine threads.Head typesHexagon head,Mushroom head,Pan head ... 20 GP container :22.6T-25.5Tadditioal processes Washer assembly,Heat treatment,Baking hydrogen,Anti-slipping patch ... than 20 years experiences in screw,bolt,nut,washer,rivet, stud, pin,wrench and so on ... most of places such as drywall,concrete,chipboard,machine,wood...2) Main export market:North America ...