Flat Head, Combo Drive, Coarse thread Double Auger Point Self Counter Sinking Screw #8 x 1-5/8", box of 100 Type 17 Double Auger Point for Quicker penetration Coarse Deep Thread for better driving/holding Flat Head with 4 nibs for self countersinking Smooth shank for better draw and tighter seating Side cutter drills its own pilot hole