In addition to a Torx-head design that eliminates cam-out slippage, these innovative self-countersinking screws feature six cutting pockets beneath the head and sharp, saw-like lower threads to drive through a variety of materials smoothly, without tearing. Ideal for exterior purposes such as building a deck. Available in several lengths and sizes. Torx/Star-head driver bits also available. The R4â„¢ is a multi-purpose screw that can be used in all woodworking and plasticapplications. Great for: Wood Cement Fiber Board Particle Board Composite Decking Plastic Wood Decking Sheet Metal Melamine Additional features: R4 CLIMATEKâ„¢ coated screws are tested and approved for all exterior applications including pressure treated lumber as stated in the ICC report #ESR-2442. Sub-head cutters create clean countersunk holes without damaging the surface- even in brittle materials. Eliminates pre-drilling in most cases Fits perfectly into existing countersunk holes on hinges and other hardware fittings. Screws 2" long or longer have special CEE thread that enlarges screw hole and improves performance.