Value Collection 581759BR Hex Socket Cap Screw 7/8-9 Unc

Product Description

The Value Collection 581759BR is a hex socket cap screw designed for high-strength fastening applications in industrial, mechanical, and structural assemblies. Manufactured from alloy steel with a black oxide finish, this screw delivers corrosion resistance and a clean matte appearance suited for close-tolerance work. The 7/8-9 UNC thread profile and 1-3/4 inch length under head make it appropriate for medium-to-heavy clamping loads. Drive engagement is achieved through a 3/4-inch internal hex socket, requiring a matching hex key or Allen-type driver. This fastener is partially threaded, providing a stronger grip in the shank area and precise alignment in clearance holes. Machinists, millwrights, and mechanical contractors are the typical installers.

This cap screw is suited for use in general industrial machinery, heavy equipment, tooling fixtures, and structural mechanical assemblies where a recessed-drive, high-strength fastener is required. The 7/8-9 UNC coarse thread is widely used in ferrous and alloy steel applications where quick assembly and strong thread engagement are priorities. The black oxide coating also reduces light reflection and provides mild corrosion protection in dry or lightly oiled environments.

Key Features

• 7/8-9 UNC coarse thread for fast assembly and strong engagement in alloy steel assemblies
• 1-3/4 inch length under head with partial threading for shank strength and alignment
• 3/4-inch hex socket drive for high-torque input using standard hex keys or drivers
• Alloy steel construction for elevated tensile and shear strength
• Black oxide finish provides a matte appearance and mild corrosion resistance
• Meets ASME/ANSI B18.3 and ASTM A574 standards for dimensional and mechanical compliance

Compatibility

Designed as an OEM-style or replacement hex socket cap screw for industrial machinery, structural fixtures, and mechanical assemblies requiring a 7/8-9 UNC partially threaded fastener with a 3/4-inch hex socket drive.

Installation Notes

Installation is typically performed by machinists, millwrights, or mechanical contractors using a calibrated torque wrench and the appropriate 3/4-inch hex key or bit. De-energize and lock out all equipment before fastener removal or installation per applicable OSHA lockout/tagout procedures. Do not substitute a smaller drive tool, as rounding the socket will damage the fastener and require extraction. Inspect thread engagement depth before final torque to ensure proper clamping.