#8 x 1-1/2 Inch Black Oxide Hardened Steel #2 Point Pan Head Self-Drilling Tek ScrewSquare Drive Pan head self drilling screws have a self driller cutting (TEK) point to pierce through 20 to 14 gauge metals. The heads use a square bit #1 through #3 driver depending on the size of the screw. These screws are used in the exterior elements. Square Drive screws are preferred by some over traditional Phillips Drives because the Square Drive allows for a higher torque installation reduces cam out and reduces screw stripping when compared