GRK Fasteners RSS Structural Screw 5/16" x 4" Handy Pack

GRK’s RSS Structural Screws are engineered as a high-performance alternative to traditional lag screws, delivering professional-grade holding power with significantly less effort. Each 5/16" x 4" screw features a built-in washer head and Climatek® coating, making it ideal for both interior and exterior structural applications, including treated lumber. This Handy Pack contains 25 screws—perfect for deck posts, stair rails, ledger boards, playground equipment and more.

Built around proprietary Zip-Tip and W-Cut technologies, RSS screws drive smoothly into most woods without pre-drilling or cam-out, while precision cutting pockets reduce splitting. Code-approved under ESR-3201, these rugged fasteners offer unmatched strength and reliability on every job site.

Key Features

• Zip-Tip point for self-drilling, faster penetration
• W-Cut thread for low-torque, effortless driving
• CEE thread profile delivers a clean, finished look
• Climatek® coating resists corrosion; AC257 code-approved for treated lumber
• Washer head for maximum pull-out resistance
• Precision cutting pockets minimize splitting and bore clean holes
• Zero-stripping, recessed star drive (T-25)
• ESR-3201 approved for structural use