self drilling and self tapping screw 1.Head tpye:HWH,HFH,PAN HEAD,FLAT HEAD,BUGLE ... ,#12,#14 self drilling and self tapping screw SUPPLIER:Material:carbon steel C1022 or C1018Finish:zinc plated,painting,dacromat,RuspertSize:#6,#7,#8,#10 ... capacity,timely delivery,competitive price self drilling and self tapping screw