Value Collection 581755BR Hex Socket Cap Screw 7/8-9 Unc

Product Description

The VALUE COLLECTION 581755BR is a hex socket cap screw designed for high-strength fastening in mechanical assemblies, tooling, and structural applications. Manufactured from alloy steel with a black oxide finish, this fastener delivers solid clamping force and corrosion resistance in demanding environments. The 7/8-9 UNC thread profile follows Unified National Coarse standards, and the 1-1/4 inch length under head suits moderate-depth through-bolting and tapped-hole applications. A 3/4 inch hex drive accommodates standard hex keys and Allen drivers. This screw is specified and installed by machinists, millwrights, maintenance mechanics, and fabricators working to ASME/ANSI and ASTM standards.

This fastener is used across industrial, commercial, and OEM applications wherever a recessed-drive, high-strength cap screw is required. Common install scenarios include machine frames, fixtures, tooling plates, and equipment mounts. The partially threaded shank provides a bearing shoulder for precision alignment in bolted joints. It is suitable for use in steel, cast iron, and other ferrous assemblies where the 7/8-9 UNC thread pitch is specified by the original design or maintenance standard.

Key Features

• 7/8-9 UNC thread — coarse pitch for fast engagement in tapped holes
• 1-1/4 inch length under head — suits moderate-depth fastening applications
• Alloy steel construction — high tensile and shear strength per ASTM A574
• Black oxide finish — mild corrosion resistance and reduced light reflection
• Partially threaded shank — provides shoulder bearing for accurate joint alignment
• 3/4 inch hex drive — compatible with standard hex keys and drive tools

Compatibility

Designed as an OEM-style and replacement fastener for applications specifying a 7/8-9 UNC hex socket cap screw per ASME/ANSI B18.3 and ASTM A574 standards.

Installation Notes

Installation is performed by qualified mechanics, machinists, or maintenance technicians using a 3/4 inch hex key or Allen driver. Ensure the mating tapped hole is clean, properly threaded to 7/8-9 UNC, and free of debris before installation. Follow the torque specifications prescribed by the equipment manufacturer or applicable engineering standard for the joint material and fastener grade. Do not substitute a lower-grade fastener in applications where ASTM A574 alloy steel is specified.