Value Collection MP39040-1 Hex Cap Screw 5/16-18 Grade 8 25pk

Product Description

The VALUE COLLECTION MP39040-1 is a Grade 8 steel hex head cap screw engineered for high-strength fastening applications. It features a 5/16-18 UNC thread and a 4-1/2 inch length under head, with partial threading along the shank. The zinc yellow dichromate finish provides corrosion resistance and serves as a visual identifier for Grade 8 hardware. Manufactured to ASME B18.2.1 standards, this fastener delivers the dimensional consistency and tensile strength required in demanding mechanical, structural, and equipment assembly applications. Each order contains 25 screws.

This cap screw is suited for use in industrial machinery, mechanical assemblies, structural brackets, and equipment fabrication where high-strength inch-series fasteners are specified. The partial threading is appropriate for clamping applications where a full-thread grip length is not required or where a smooth shank is needed through the clamped material. Maintenance technicians, millwrights, and mechanical contractors commonly use Grade 8 hardware of this type in both new construction and retrofit work.

Key Features

• Grade 8 steel construction for high tensile and proof load strength
• 5/16-18 UNC thread for standard inch-series fastener compatibility
• 4-1/2 inch length under head suits deep-reach clamping applications
• Partial threading provides a smooth shank section for clean clamping interfaces
• Zinc yellow dichromate finish offers corrosion resistance and Grade 8 visual identification
• Manufactured to ASME B18.2.1 for consistent dimensional tolerances

Compatibility

Designed as a standard inch-series Grade 8 hex head cap screw for use with 5/16-18 UNC threaded holes, nuts, and inserts in steel, cast iron, and similar structural materials.

Installation Notes

Installation is performed by mechanical technicians and tradespeople using a standard hex socket or open-end wrench. Always confirm the mating thread is 5/16-18 UNC before installation and inspect threads for damage before torquing. Do not mix Grade 8 fasteners with non-Grade-rated nuts unless the assembly is engineered for that combination. Follow applicable torque specifications from the equipment manufacturer or a recognized fastener standard for the joint material and finish type.