Value Collection 721283BR Flat Socket Cap Screw 5/8-18

Product Description

The VALUE COLLECTION 721283BR is a flat socket cap screw designed for flush or countersunk fastening applications in mechanical assemblies, tooling, and structural components. It features an 82-degree flat head with a 3/8-inch hex socket drive, allowing installation with a standard hex key or Allen wrench. The fastener measures 5/8-18 UNF thread by 3-1/2 inches in overall length and is partially threaded. Constructed from alloy steel with a black oxide finish, it provides solid mechanical strength with moderate corrosion resistance in dry or lightly oiled environments. Machinists, millwrights, and maintenance technicians are the typical installers.

This screw is suited for applications requiring a low-profile, countersunk head that sits flush with or below a mating surface. Common uses include machine tool fixtures, jigs, equipment frames, and fabricated steel assemblies where a protruding head would interfere with adjacent components or mating parts. The 5/8-18 UNF thread pitch is a fine-thread designation, making it appropriate where vibration resistance or precise axial adjustment is needed. The partial threading allows for a smooth shank section under the head, which can improve shear strength in certain joint configurations.

Key Features

• 82-degree flat head profile seats flush in standard countersunk holes
• 3/8-inch hex socket drive for high-torque installation with a hex key
• 5/8-18 UNF fine-thread form resists loosening under vibration
• Partially threaded shank improves shear load capacity in bolted joints
• Alloy steel construction provides high tensile and yield strength
• Black oxide finish offers a clean appearance with light surface protection

Compatibility

Designed as a standard-dimension replacement or maintenance fastener conforming to ASME/ANSI B18.3 and ASTM F835 for flat socket cap screws in inch-series UNF applications.

Installation Notes

Installation is typically performed by machinists, millwrights, or maintenance mechanics using a 3/8-inch hex key or T-handle driver. Ensure the mating countersink is machined to an 82-degree included angle to achieve full head seating. De-energize and lock out any equipment before fastener service in accordance with applicable OSHA lockout/tagout procedures. Do not substitute this fine-thread UNF fastener in holes tapped for UNC thread without verifying thread engagement.