... etc 4.ISO9001,ISO14001,TS16949. Products Nameself taping screw SizeM1.0~M4.0 Material Carbon steel,stainless steel ... precision screws,machine screw,hard disk screws,self tapping screw,nylock patch screw,waterproof sealing screws,color head screw and precision ... such as hard disk screw, self tapping screw, patch screw, water-proof sealing screw, head colored screw, special use screw as well as precision ...