Quik Drive DTHQ3S Trim Head Screw for Deck and Dock 3-Inch with Quik Guard Corrosion Protection Quik Guard proprietary double barrier corrosion protection Composite Deck to Wood Screw Nibs under head for countersinking Used in Quik Drive Tools PRO300S, 2000 SDS. Free Bit in every box of screws #2 Undersized square drive BIT2SU