5/16 x 3 Hex Lag Scrw HDG

Overview

The 5/16 x 3 Hex Lag Screw HDG (05570) is designed for heavy-duty timber fastening and structural wood-to-masonry or wood-to-concrete applications.

Technical Features

• Hot-Dip Galvanized (HDG) finish: Provides a thick, metallurgically bonded zinc coating for corrosion resistance, making this fastener suitable for outdoor, treated lumber, and moisture-exposed environments.
• Hexagonal head design: Accepts standard socket or wrench drive, enabling high-torque installation without head cam-out or stripping.
• 5/16-inch diameter: Provides a substantial shank cross-section capable of bearing significant shear and withdrawal loads in structural assemblies.
• 3-inch length: Delivers sufficient thread engagement depth for secure fastening through dimensional lumber and into substrate materials.
• Lag screw thread form: Coarse, gimlet-pointed thread design self-taps into wood fiber, eliminating the need for a nut and providing high withdrawal resistance.

Applications

• Fastening heavy timbers to one another in structural framing, decking, and post-beam construction.
• Securing wood members to masonry or concrete substrates when used with an appropriate anchor or sleeve.
• Outdoor and exposed structural connections where corrosion resistance is required due to the HDG coating.
• General heavy-duty wood construction requiring a wrench-driven, high-strength fastener.