Stainless #8 x 1/2" Philips Pan Head Self Drilling Sheet Metal Tek Screws With Drill Point, (1/2" To 1" Length in Listing), 100 pieces (#8 x 1/2") Usa a Philips P2 bit for #8 Screws Tensile - 180,000 psi, Hardness - 40 Rockwell C This is a tapping screw with spaced threads and a drill point which drills its own hole Great for using on Gutters! 410 Stainless