Value Collection 489082PS Carriage Bolt 3/8-16 4 in Square Neck

Product Description

The VALUE COLLECTION 489082PS is a 3/8-16 UNC carriage bolt with a 4-inch length under head and a square neck designed to resist rotation during installation. Manufactured from Grade 2 steel with a zinc-plated finish, this fastener meets ASTM A307 standards for general-purpose structural and mechanical applications. The square neck beneath the domed head seats into pre-drilled square holes or bites into wood to prevent spinning as the nut is tightened. Licensed contractors, maintenance technicians, and trade professionals rely on this bolt type for through-bolted connections in light structural assemblies, HVAC equipment mounting, and general mechanical work.

This carriage bolt is suited for residential and light commercial applications where a flush, rounded head is required on the visible face of the assembly. Common install scenarios include securing brackets, frames, panels, and equipment bases where the fastener passes through wood, metal, or composite material. The zinc-plated finish provides basic corrosion resistance appropriate for dry to mildly humid environments. Sold in multiples, this bolt is a standard stock item for field crews and shop inventory alike.

Key Features

• 3/8-16 UNC thread size for broad hardware compatibility
• 4-inch length under head accommodates typical through-bolt connections in structural and equipment-mounting applications
• Square neck prevents rotation during tightening without requiring a wrench on the bolt head
• Grade 2 steel construction meets ASTM A307 standards for general-purpose fastener loads
• Zinc-plated finish provides corrosion resistance in dry to mildly humid environments
• Domed head leaves a clean, low-profile face on the accessible side of the joint

Compatibility

Designed as a general-purpose UNC carriage bolt compatible with standard 3/8-inch through-bolt hardware, nuts, and washers conforming to inch-system fastener specifications.

Installation Notes

Installation is performed with a standard wrench or socket on the nut side; no tool is applied to the bolt head. Ensure the square neck seats fully into the mating hole to prevent spinning before torquing the nut. Follow applicable structural or equipment manufacturer fastener specifications when determining final torque. Confirm the zinc-plated finish is appropriate for the service environment before installation in outdoor or high-humidity locations.