S-91253A836 3/4"-16 x 3" 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.
• Precise Class 3A thread fit provides superior engagement and vibration resistance, maintaining joint integrity in demanding environments.
• Black-oxide coating on alloy steel offers enhanced corrosion resistance and a durable, non-reflective finish for long-lasting use.
• 1/2" hex drive design allows for high-torque installation with standard tools, speeding up assembly and reducing labor time.
• 82° countersink angle and flat head profile enable a flush, secure fit in pre-drilled holes, minimizing protrusion and improving safety.
• Fully threaded UNF fine spacing ensures maximum grip and load distribution along the entire 3" length, ideal for thick materials.
• Rockwell C37 hardness provides excellent wear resistance, extending the screw's service life in repetitive or abrasive conditions.

Professional Applications & Engineering Value

This 3/4"-16 UNF flat head screw is engineered to address critical challenges in industrial assembly, where vibration loosening and material fatigue are common concerns. The black-oxide alloy steel construction, combined with a Class 3A thread fit, ensures tight tolerances and reliable performance in machinery, structural frameworks, and heavy equipment. The fine thread spacing and fully threaded design enhance load-bearing capacity, making it suitable for applications requiring secure fastening in thick metal or composite materials. Its 82° countersink angle allows for a seamless, low-profile installation, reducing snag risks and improving aerodynamic or aesthetic finishes in automotive, aerospace, and construction sectors.

Specification Summary & Compliance

This screw adheres to Class 3A thread fit for precise dimensional accuracy and UNF thread standards with fine spacing. It meets ASTM F835 specifications for mechanical properties and is compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring environmental safety and material reliability in global supply chains.