Value Collection 721259PR Flat Socket Cap Screw 1/2-20

Product Description

The VALUE COLLECTION 721259PR is a flat socket cap screw designed for applications requiring a flush or countersunk fastener profile. Sized at 1/2-20 UNF x 3-1/2 inches overall length, it features a 82-degree flat head driven by a 5/16-inch hex socket. Constructed from alloy steel with a black oxide finish, this screw delivers solid corrosion resistance and mechanical strength. It is partially threaded along its shank, which helps maintain clamping load and alignment in precision assemblies. Machinists, millwrights, and maintenance technicians install this type of fastener in metal fabrication, tooling, and mechanical assembly work.

This flat socket cap screw suits applications where a standard button or pan head would protrude above the mating surface. The countersunk 82-degree flat head seats flush when installed into a properly chamfered hole. Typical use cases include jigs and fixtures, machine frames, die sets, and structural steel assemblies where a clean surface profile is required. The 1/2-20 UNF thread pitch is a fine-thread standard commonly specified in precision mechanical and aerospace-adjacent industrial work.

Key Features

• 82-degree flat head profile seats flush in countersunk holes
• 5/16-inch hex socket drive for standard allen key or hex bit tools
• 1/2-20 UNF fine-thread for precise clamping and reduced loosening under vibration
• Partially threaded shank for improved alignment and shear resistance
• Alloy steel construction with black oxide finish for corrosion resistance
• Meets ASME/ANSI B18.3 and ASTM F835 fastener standards

Compatibility

Designed as a standard-dimensioned replacement or stock fastener for applications specifying a 1/2-20 UNF flat socket cap screw per ASME/ANSI B18.3 and ASTM F835.

Installation Notes

Installation requires a properly countersunk hole machined to match the 82-degree head angle. Use a calibrated hex key or socket bit sized at 5/16 inch to avoid rounding the drive. De-energize or lock out any equipment before fastener removal or installation in accordance with applicable OSHA lockout/tagout procedures. Do not exceed the rated mechanical load for the fastener size and material grade.