Value Collection 211129PR Flat Socket Cap Screw 1/4-28

Product Description

The VALUE COLLECTION 211129PR is a flat socket cap screw designed for flush or countersunk fastening applications in metal and structural assemblies. It features an 82-degree flat head profile and a 5/32 inch hex socket drive, accepting a standard hex key or Allen wrench. The screw is fully threaded along its 1 inch overall length with a 1/4-28 UNF thread, making it suitable for fine-thread applications where vibration resistance or precise thread engagement is required. Constructed from alloy steel with a black oxide finish, it offers solid mechanical strength with moderate corrosion resistance in dry or lightly oiled environments. Machinists, fabricators, and maintenance technicians commonly install this fastener.

This flat socket cap screw is used in applications requiring a low-profile or flush-mount fastener head, such as machine frames, fixtures, jigs, tooling plates, and mechanical assemblies. The 1/4-28 UNF fine thread is well-suited for tapped holes in steel, aluminum, and similar materials where a fine thread pitch improves holding strength. Fully threaded construction provides maximum thread engagement across the full 1 inch length, which is useful in thin material applications or when the fastener is used with a nut.

Key Features

• 82-degree flat head profile for flush or countersunk seating
• 5/32 inch hex socket drive compatible with standard Allen keys
• 1/4-28 UNF fully threaded, 1 inch overall length
• Alloy steel construction meets ASME/ANSI B18.3 and ASTM F835 standards
• Black oxide finish for a low-reflectance appearance and mild corrosion inhibition

Compatibility

Designed as an OEM-style or replacement flat socket cap screw for standard 1/4-28 UNF countersunk hex socket applications conforming to ASME/ANSI B18.3 and ASTM F835.

Installation Notes

Installation is performed with a 5/32 inch hex key or Allen wrench; use a properly calibrated torque tool where fastener preload is critical to the application. Ensure the mating countersink angle matches the 82-degree flat head geometry before installation to achieve full head seating. Confirm the tapped hole or nut thread class is compatible with 1/4-28 UNF before driving the fastener. Black oxide finish provides limited corrosion protection and should not be used as a substitute for plated or stainless fasteners in wet or outdoor environments without additional lubrication or sealing.