Value Collection 211221PR Flat Socket Cap Screw 3/8-16

Product Description

The VALUE COLLECTION 211221PR is a flat socket cap screw designed for applications requiring a flush or countersunk fastener profile. It features an 82-degree flat head with a 7/32-inch hex socket drive and a 3/8-16 UNC thread on a 2-1/4-inch overall length. The shank is partially threaded, making it well suited for clamping applications where an unthreaded grip area is needed. Manufactured from alloy steel with a black oxide finish, this screw delivers solid mechanical strength and moderate corrosion resistance in typical indoor or protected environments. Machinists, millwrights, and general maintenance mechanics commonly install this fastener type.

This flat socket cap screw is used in machine assemblies, fixtures, tooling plates, and structural fabrications where the screw head must sit flush with or below the mating surface. The hex socket drive allows installation with a standard hex key or Allen driver in tight clearance areas where a wrench cannot reach. The 3/8-16 UNC thread is a widely used coarse-thread standard compatible with standard tapped holes, threaded inserts, and hex nuts in inch-based assemblies. Typical installation environments include manufacturing equipment, industrial machinery, and mechanical fixtures.

Key Features

• 82-degree flat head profile seats flush in standard countersunk holes
• 7/32-inch hex socket drive for use with standard Allen keys or hex bit drivers
• 3/8-16 UNC coarse thread standard for broad compatibility with inch-system tapped holes
• Partially threaded shank provides an unthreaded grip zone for clamping applications
• Alloy steel construction meets ASME/ANSI B18.3 and ASTM F835 fastener standards
• Black oxide finish reduces surface reflectivity and provides light corrosion resistance

Compatibility

Designed as a standard inch-series flat socket cap screw for use in any application requiring a 3/8-16 UNC countersunk fastener per ASME/ANSI B18.3 and ASTM F835 specifications.

Installation Notes

Installation is performed with a 7/32-inch hex key or Allen driver. Ensure the mating hole is countersunk to an 82-degree included angle to achieve full head seating. Power down or de-energize any equipment before fastener removal or installation on live machinery. Black oxide finish is not a heavy-duty corrosion barrier; apply supplemental lubricant or coating if the fastener will be exposed to moisture or corrosive environments.