Hillman Fasteners 240180 Carriage Bolt 3/8-16 X 4 in 50 Pack

Product Description

The HILLMAN FASTENERS 240180 is a 3/8-16 x 4 inch steel carriage bolt designed for through-bolting wood, metal, and composite materials in structural and general-purpose fastening applications. It features a round dome head that sits flush against the work surface and a square neck that bites into wood to prevent rotation during tightening. The coarse thread pitch (3/8-16 UNC) provides strong clamping force and resists loosening under vibration. Sold in a 50-count box, this fastener suits contractors, maintenance technicians, and trade professionals who need reliable quantity stock on the job.

This carriage bolt is commonly used in wood framing, deck construction, equipment mounting, and structural assemblies where a smooth finished head is required on one face. The square neck seats into pre-drilled holes in lumber or soft materials, eliminating the need for a second wrench on the bolt side. It is suitable for both interior and exterior structural connections when used with appropriate corrosion-resistant hardware and coatings as required by the application environment.

Key Features

• 3/8-16 UNC coarse thread for strong clamping and vibration resistance
• 4 inch length accommodates multi-layer or thick-material through-bolting
• Round dome head provides a clean, low-profile finished surface
• Square neck prevents bolt rotation during nut tightening without a second tool
• Steel construction for high tensile strength in structural fastening
• 50-count box quantity suited for production work and job-site stocking

Compatibility

Designed as a standard 3/8-16 UNC carriage bolt for use with 3/8-16 hex nuts and washers in wood and light structural assemblies. Fits standard 3/8 inch clearance holes.

Installation Notes

Installation is typically performed by carpenters, general contractors, or maintenance trades using a standard wrench or socket on the nut side. Drill a clearance hole sized to allow the square neck to seat fully into the material before driving the bolt through. Tighten the nut with a wrench while the square neck locks the bolt in place. Consult applicable building codes for required fastener grades and corrosion protection when used in structural or exterior applications.