GRK RSS Black Structural Screw is a structural fastener designed for ease of installation and the strongest of connections while providing a bold finish. With proprietary features like the Zip-Tip, and W-Cut thread, RSS fasteners drive into most woods without the need for pre-drilling. The specially engineered design results in a low-effort installation, especially compared to conventional lag screws. RSS Rugged Structural Screws have a Climatek Coating for installation in both interior and exterior conditions where exposure to moisture is intermittent and is code-approved for use in treated lumber. threads and point bite instantly into material (including hardwood), reducing the splitting effect caused by smaller shanks. Its washer type head has no sharp edges like conventional lag screws and the added shoulder underneath the washer has the ability to center the RSS screw in predrilled hardware. This product is engineered for dependable performance, ease of installation, and long-term durability in demanding applications.