Check the listing for details. GRK Fasteners RSS™ 5/16 x 3-1/2 Inch, Rugged Structural Screws, 500 PCS, Rust. Condition: New. Listed at 239.36 USD. The GRK RSS Rugged Structural Wood Screw is a professional-grade fastener designed for heavy-duty framing, decking, and construction projects. These premium screws deliver superior performance in applications, including deck building, timber framing, laminated beams, pole barns. GRK’s Climatek™ coating, provides exceptional corrosion resistance, making these construction screws ideal for pressure-treated lumber, cedar, and all other wood applications. The patented Fast Bite Tip and Zip-Tip™ technology eliminates the need for pilot holes, while the W-Cut™ design ensures smooth, low-torque driving in all wood types. ICC-ES ESR-2442 approved for structural applications, these self-drilling screws are trusted by professional builders and DIYers alike.