WASHER,LOCK WASHER,spring 1.ISO,ANSI,JIS,DIN,BS& ... 8 ,6.8,8.8,9.8... WASHER,LOCK WASHER ,SPRING LOCK WASHERS. A good non-standard fastenerS manufacturer for ... drywall screw;Type "M","UNC","UNF","BSW"threads for Machine threads.Head typesHexagon head,Mushroom head,Pan head,Countersunk ... in most of places such as drywall,concrete,chipboard,machine,wood...2) Main export market:North America,South America ...