chamfering cross self tapping screw material:c1022 surface: yellow,black oxide,white 1)Name: chamfering cross self tapping screw or self tapping screw 2)material:A3 Steel3)surface finish: yellow and white zinc or black oxide4) size:5*(25,30,35,40,45,50,60) 6*(25,30,35,40,50,60)5)samples free6)Our items are best quality and reasonable price. chamfering phillip head tapping screw