ITW TEKS SELF-DRILLING SCREW W/ WINGS, PHILLIPS FLAT HEAD, 21386, #12 X 2-3/4" HELP SECURE WOOD TO METAL WITHOUT PRE-DRILLING. THE STEEL SCREW IS IDEAL FOR USE WITH METAL OF A THICK GAUGE. SPECIAL WINGS REAM A HOLE IN THE WOOD TO PREVENT THREAD ENGAGEMENT DURING DRILLING. NO PRE-DRILLING REQUIRED. FEATURES: USE TO FASTEN WOOD TO METAL IDEAL FOR USE WITH METAL OF A THICK GAUGE SCREWS TAP THEIR OWN THREADS STEEL CONSTRUCTION FOR STRENGTH 2-3/4 IN. LONG ZINC PLATED FLAT HEADS, PHILLIPS DRIVES AND FINE THREADS DRILL POINT AND FLUTE REMOVE MATERIAL AND SIZE HOLES FOR THREADS