Value Collection D39040 Hex Head Cap Screw 5/16-18 X 4 in

Product Description

The VALUE COLLECTION D39040 is a Grade 8 steel hex head cap screw with a 5/16-18 UNC thread and a 4-inch length under head. Partially threaded and finished with a zinc yellow dichromate coating, this fastener is built for high-strength bolted connections in demanding applications. Grade 8 steel delivers a higher tensile strength than standard Grade 5 hardware, making it suitable for structural, mechanical, and equipment assembly work. The zinc yellow dichromate finish provides corrosion resistance appropriate for general industrial and mechanical use. It conforms to ASME B18.2.1 dimensional standards, ensuring consistent fitment with standard hex nuts and washers.

This cap screw is used across a broad range of trade and industrial applications including HVAC equipment assembly, electrical panel and enclosure mounting, plumbing equipment supports, and general mechanical installations. The 5/16-18 UNC coarse thread is one of the most common thread profiles in North American trade hardware, fitting standard tapped holes and hex nuts of matching size. Partial threading allows for a smooth shank section, which is preferred in applications where the shank bears shear load or where precise clamp length is needed.

Key Features

• Grade 8 steel construction for high tensile strength bolted connections
• 5/16-18 UNC coarse thread — widely compatible with standard hardware
• 4-inch length under head for deeper reach in structural assemblies
• Partially threaded shank supports shear-load and clamp-critical applications
• Zinc yellow dichromate finish provides corrosion resistance for general service
• Conforms to ASME B18.2.1 for consistent dimensional compliance

Compatibility

Designed for use with standard 5/16-18 UNC hex nuts, lock nuts, and washers conforming to inch-series fastener standards. Suitable for any application requiring an ASME B18.2.1-compliant Grade 8 hex head cap screw in this thread and length combination.

Installation Notes

Installation is performed by mechanics, millwrights, HVAC technicians, plumbers, and electricians as part of equipment assembly or structural mounting tasks. Ensure mating tapped holes or nuts match the 5/16-18 UNC thread specification before installation. Do not exceed the rated tensile load of Grade 8 fasteners by applying impact tools beyond snug-tight without a torque specification from the equipment manufacturer. Inspect the zinc dichromate finish for damage before use in corrosive environments and replace if coating integrity is compromised.