Torx Drive Deck Screws: A countersunk head with a Torx recess socket. The underside of the countersunk head has nibs for a clean fit and hold, the last few threads of the screw taper to an extra sharp point with a groove cut out (Type 17 Point) which enables the screw to drive better without pre-drilling a pilot hole. Prime Guard Plus Coating for exterior applications, including decks, siding and gazebos. Approved for pressure treated lumber. Driver bit needed for all sizes is a Torx 25 driver bit.