Cap Screws Flat Socket Alloy Thermal Black Oxide 5/16-18 X 2 1/2 are high-strength fasteners designed for dependable assembly in machinery, automotive, and industrial equipment. Featuring a flat socket head, these cap screws sit flush to maintain a clean, professional finish in tight spaces.

Constructed from alloy steel and finished with a thermal black oxide coating, they combine strength with a durable, low-gloss appearance suitable for wet, oily, or dusty environments where corrosion protection is adequate for standard industrial use.

Key Features

• Thread size: 5/16-18 UNC
• Length: 2-1/2 inches
• Flat socket head cap screw
• Material: Alloy steel
• Finish: Thermal black oxide

Specifications

• Thread: 5/16-18 UNC
• Length: 2-1/2 in
• Head style: Flat socket
• Drive type: Hex socket
• Material: Alloy steel
• Finish: Thermal black oxide

Applications

• Machinery assembly
• Automotive and heavy equipment
• Industrial manufacturing and maintenance

Why choose these cap screws? They provide a strong, reliable fastening solution with a low-profile head that reduces snag risk in confined spaces. The thermal black oxide finish adds a durable, professional appearance and helps conceal wear over time. Ideal for standard industrial environments where 5/16-18 UNC threads and 2-1/2″ length are required.