Value Collection 218377MSC Carriage Bolt 3/4-10 8 in Grade 8

Product Description

The VALUE COLLECTION 218377MSC is a fully threaded carriage bolt designed for high-strength fastening applications in structural, mechanical, and industrial assemblies. Built to Grade 8 alloy steel with a zinc trivalent chromate finish, this bolt delivers excellent tensile strength and corrosion resistance. It features the standard domed head and square neck profile that locks against a substrate when driven through a hole, preventing rotation during nut installation. Sized at 3/4-10 UNC thread with 8 inches of length under the head, it is fully threaded from the neck to the end. The zinc trivalent chromate coating meets modern environmental standards while providing reliable surface protection.

This carriage bolt is suited for heavy-duty construction, machinery mounting, wood-to-metal connections, and structural framing where a flush, rotation-resistant fastener head is required. Its Grade 8 rating makes it appropriate for high-load applications that demand greater proof load and tensile strength than Grade 5 or lower hardware. Installers in HVAC equipment mounting, electrical enclosure framing, plumbing equipment support, and general mechanical work will find this bolt a reliable choice where 3/4-10 UNC fasteners are specified.

Key Features

• Grade 8 alloy steel construction for high tensile and proof load capacity
• Zinc trivalent chromate finish provides corrosion resistance and meets RoHS-aligned coating standards
• Fully threaded from square neck to end along the full 8-inch shank length
• Square neck design prevents bolt rotation during nut tightening without requiring a wrench on the head
• 3/4-10 UNC thread standard per SAE J429
• Domed head profile for clean, snag-resistant appearance on the bearing surface

Compatibility

Designed as a standard 3/4-10 UNC fully threaded carriage bolt for use in applications requiring SAE J429 Grade 8 fasteners with a square neck and 8-inch length under the head.

Installation Notes

Installation is performed by passing the bolt through a pre-drilled or punched hole sized to allow the square neck to seat and bite into the material, resisting rotation. A standard torque wrench and the appropriate hex nut and washer are used to draw up the assembly from the nut side only. Always ensure hole diameter is sized correctly for the square neck to engage. Follow applicable structural or mechanical codes when specifying Grade 8 fasteners in load-bearing assemblies.