... screw;Type "M","UNC","UNF","BSW"threads for Machine threads.Head typesHexagon head,Mushroom head,Pan head, ... nut,washer,rivet, stud, pin,wrench and so on .2. Our company had good reputation with customers ... .3.As a credible manufacturer we are ,we can't jerry-build ,We will actually do strength what ... most of places such as drywall,concrete,chipboard,machine,wood...2) Main export market:North America,South ...