GRK GRK-16223 5/16" x 3-1/2" RSS Structural Screws (100-Pack)The GRK RSS (Rugged Structural Screw) is a high performance alternative to traditional lag screws, designed to provide superior strength and ease of installation without the need for pre drilling. Engineered from specially hardened steel, these screws offer exceptional tensile, torque, and shear strength for critical structural applications. The 5 16" x 3 1 2" profile is specifically optimized for heavy duty framing, deck substructures, and ledger