5/16 In. X 5-1/8 In. L Star Hex Head W-Cut Structural Screws

GRK Fasteners structural screws are engineered for heavy-duty construction and outdoor applications. Made of specially hardened steel, these fasteners deliver high tensile, torque, and shear strength needed for demanding projects like deck building, ledger board installation, stair rail attachment, and structural framing. The #20 x 5-1/8 in. size with star drive head and built-in washer provides a professional-quality fastening solution.

The sharp threads and points bite instantly into material, including hardwoods, without requiring pre-drilling—reducing splitting and accelerating installation. This self-tapping design makes these screws an efficient alternative to traditional lag screws.

Features and Benefits

• W-Cut Thread Design: The specialized thread pattern pulls two substrates together tightly, creating a strong, secure joint with excellent drawing strength.
• Self-Tapping Design: Sharp threads eliminate the need for pre-drilling in most applications, reducing installation time and the risk of wood splitting.
• Hardened Steel Construction: Specially hardened steel delivers superior tensile, torque, and shear strength for demanding structural applications.
• Washer Head with Built-in Shield: The round washer head eliminates gaps between materials, centers the fastener in hardware plates, and provides a clean, professional appearance without sharp edges.
• Recessed Star Drive: Star drive design provides secure fastening control.
• CEE Thread Technology: The six-threaded CEE thread enlarges the screw hole for the non-threaded portion, reducing friction and driving torque while allowing wood to settle naturally.

Specifications

• Brand: GRK Fasteners
• Model: 14231
• Size: #20 x 5-1/8 in. Length
• Head Type: Star drive washer head (recessed)
• Thread: W-Cut CEE thread
• Material: Hardened steel
• Finish: Yellow zinc plated
• Count: 20 pack