S-91253A154 5-44 x 1/2" ASTM F835 Alloy Steel Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Exceptional tensile strength of 130,000 psi ensures reliable performance in high-stress applications, reducing the risk of fastener failure.
• Superior corrosion resistance from the black-oxide finish on alloy steel, extending service life in demanding industrial environments.
• Precise Class 3A thread fit provides tight, secure fastening with minimal play, enhancing assembly accuracy and vibration resistance.
• Full threading along the 1/2" length allows for maximum grip and uniform load distribution across the entire fastener.
• 82° countersink angle enables a flush, low-profile installation, ideal for applications where surface clearance is critical.
• Hex drive (5/64") offers easy installation and high torque transmission, speeding up assembly while minimizing tool slippage.
• Rockwell C39 hardness ensures durability and wear resistance, maintaining thread integrity through repeated use.

Professional Applications & Engineering Value

These 5-44 UNF flat head screws are engineered to address common industrial challenges such as vibration loosening and corrosion in machinery, electronics, and automotive assemblies. The fine thread design and Class 3A fit provide superior clamping force and resistance to dynamic loads, making them ideal for precision equipment where reliability is paramount. Made from black-oxide alloy steel, they offer enhanced protection against rust and wear, ensuring long-term performance in harsh conditions. The combination of high tensile strength and full threading allows for secure fastening in thin materials or tight spaces, reducing the need for additional components and simplifying maintenance.

Specification Summary & Compliance

This screw features a 5-44 UNF fine thread with Class 3A precision fit and right-hand threading for consistent engagement. It complies with ASTM F835 specifications for mechanical properties and is fully RoHS 3 and REACH compliant, ensuring environmental safety and regulatory adherence. Dimensions include a 1/2" length, 0.281" head diameter, and 82° countersink angle, meeting strict industrial standards for dimensional accuracy and performance.