S-91253A859 3/4"-10 x 5 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 under high-stress conditions, reducing the risk of fastener failure in demanding applications.
• Black-oxide coating on alloy steel provides enhanced corrosion resistance, extending service life in harsh industrial environments.
• Class 3A thread fit offers superior precision and tighter tolerances for secure, vibration-resistant assemblies.
• 1/2" hex drive and flat head design allows for easy installation and a flush finish, minimizing protrusion in assembled structures.
• Partially threaded shank enables better clamping force control and is ideal for applications where unthreaded grip length is critical.
• Compliance with ASTM F835, RoHS 3, and REACH ensures adherence to rigorous industry standards and environmental safety regulations.
• Coarse UNC threading facilitates quicker assembly and disassembly, improving efficiency in maintenance and repair operations.

Professional Applications & Engineering Value

Engineered for heavy-duty industrial applications, this 3/4"-10 UNC flat head screw addresses common challenges such as vibration loosening and corrosion in machinery, construction, and automotive assemblies. The black-oxide alloy steel construction, combined with a Rockwell C37 hardness rating, ensures durability and resistance to wear, making it suitable for high-load environments. Its partially threaded design provides optimal grip on materials, reducing stress concentration and enhancing joint integrity. The 82° countersink angle and standard flat head profile allow for seamless integration into surfaces, promoting aerodynamic and aesthetic finishes while maintaining structural reliability.

Specification Summary & Compliance

This screw adheres to Class 3A thread fit for precise engagement and is manufactured per ASTM F835 specifications. It features a coarse UNC thread with a diameter of 0.75" and a minimum thread length of 2". Compliance with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) confirms its environmental safety, free from hazardous substances, ensuring suitability for global industrial supply chains.