Hex Head Self Drilling Roofing Screws 1)Standard: DIN, ASTM,AS, ... Steel,SUS 3)Diameter:3.5mm~6.3mm,6#~14 Hex Head Self Drilling Roofing Screws 1)Standard: DIN, ASTM,AS ... /8"~4-1/2"5)Thread: AB TYPE,A TYPE6)Head Type:Pan Head,Flat Head,Hex Head,Bugle Head,Wafer Head ... head,oval head in cross recessed,combined,torx,slottedThread Codefull thread,half thread,or nonstandard