Hillman Fasteners 47871 Construction Lag Screws 4x5/16 20 Pack

Product Description

The HILLMAN FASTENERS 47871 is a box of 20 Power Pro Bronze Ceramic construction lag screws designed for structural and heavy-duty fastening applications. Each screw measures 4 inches in length by 5/16 inches in diameter and features a Type 17 cut point for clean, self-starting penetration into wood substrates. The Bronze Ceramic coating provides corrosion resistance rated at 1500 hours of salt spray testing, making these lags suitable for treated lumber, exterior framing, and other demanding environments. The star drive head reduces cam-out during installation. Professional carpenters, framers, deck builders, and general contractors are the primary installers.

These lag screws are suited for residential and light commercial wood construction where a high-corrosion-resistant fastener is required. Common applications include deck framing, ledger board attachment, post-to-beam connections, and structural wood assemblies that may be exposed to moisture or treated lumber chemicals. The coarse thread profile with serrated shank provides strong holding power in dimensional lumber and engineered wood products.

Key Features

• Bronze Ceramic coating rated for 1500 hours of salt spray resistance
• Type 17 cut point for self-starting installation without pre-drilling in many applications
• Star drive recess reduces cam-out during high-torque driving
• Coarse thread with serrated shank for maximum holding strength in wood
• Lifetime warranty included
• Sold in a 20-count box for job-site convenience

Compatibility

Designed as a structural lag screw for exterior and interior wood framing applications, including use with ACQ and other chemically treated lumber where standard zinc-plated fasteners are not rated.

Installation Notes

Installation is performed by carpenters, framers, and deck builders using a star-drive bit and a high-torque drill or impact driver. A pilot hole is recommended in hardwoods or near board ends to prevent splitting, even with the Type 17 cut point. Follow applicable building codes and span tables for structural connections. Do not substitute these fasteners in applications requiring engineer-specified hardware without confirming equivalence.