Value Collection 721336BR Flat Socket Cap Screw 1-1/4-7x4

Product Description

The VALUE COLLECTION 721336BR is a flat socket cap screw designed for applications requiring a flush or countersunk fastener profile. It features an 82-degree flat head driven by a 7/8-inch hex socket and is fully threaded along its 4-inch overall length. The thread size is 1-1/4-7 UNC, conforming to ASME/ANSI B18.3 and ASTM F835 standards. Constructed from alloy steel with a black oxide finish, this screw offers solid mechanical strength and moderate corrosion resistance in controlled environments. Machinists, millwrights, and maintenance technicians typically install this fastener in structural assemblies, machine frames, and fixture work where a low-profile head is required.

This flat socket cap screw is suited for heavy industrial and mechanical assembly applications where a standard hex bolt head would interfere with mating surfaces or adjacent components. The UNC thread form and inch-system dimensions make it compatible with standard tapped holes in steel, cast iron, and aluminum workpieces. Fully threaded construction provides consistent clamping force across the full grip length, which is useful in thinner material stack-ups or when maximum thread engagement is needed in a blind hole.

Key Features

• 82-degree flat head profile allows flush or countersunk installation in mating surfaces
• 7/8-inch hex socket drive for use with standard Allen keys or hex bit sockets
• Fully threaded 4-inch overall length maximizes thread engagement options
• 1-1/4-7 UNC thread size meets ASME/ANSI B18.3 and ASTM F835 fastener standards
• Alloy steel construction provides high tensile and shear strength
• Black oxide finish reduces surface reflectivity and provides mild corrosion resistance

Compatibility

Designed as a standard inch-system UNC flat socket cap screw for use in tapped holes or with matching nuts in industrial machinery, structural fixtures, and mechanical assemblies requiring a countersunk fastener per ASME/ANSI B18.3.

Installation Notes

Installation is typically performed by machinists, millwrights, or maintenance mechanics using a calibrated hex key or socket driver sized to the 7/8-inch drive. Ensure the mating hole is properly countersunk to the correct 82-degree angle before installation to achieve full head seating and prevent fastener damage. De-energize and lock out any machinery before servicing fasteners in live equipment per applicable OSHA lockout/tagout procedures. Do not use an impact driver on socket cap screws unless the tool is set to a controlled torque mode to avoid thread stripping or head damage.