S-91263A573 5/16"-18 x 3/4" 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 industrial environments, reducing the risk of fastener failure.
• Class 3A thread fit provides superior precision and tighter tolerances for secure, vibration-resistant assemblies in machinery and equipment.
• Zinc-plated alloy steel construction offers excellent corrosion resistance, extending service life in harsh or outdoor applications.
• Fully threaded design with UNC coarse threads allows for faster installation and stronger holding power in various materials.
• 82° countersink angle and flat head profile enable flush mounting for a smooth, professional finish and improved aerodynamics.
• Hex drive (3/16") ensures easy, slip-resistant installation with standard tools, boosting efficiency on the production line.
• Compliance with ASTM F835, RoHS 3, and REACH guarantees adherence to rigorous safety and environmental standards for global supply chain compatibility.

Professional Applications & Engineering Value

Engineered for demanding industrial settings, these 5/16"-18 UNC flat head screws address common challenges like vibration loosening and material fatigue. The zinc-plated alloy steel provides a durable barrier against rust and wear, ideal for automotive assemblies, construction frameworks, and heavy machinery where exposure to elements is frequent. With a coarse thread and Class 3A fit, they ensure quick, secure fastening in metals and composites, minimizing assembly time while maximizing load distribution. The 82° countersink angle allows for seamless integration into angled surfaces, reducing protrusions and enhancing safety in high-traffic areas. These screws are a trusted solution for engineers seeking high-strength fasteners that meet stringent ASTM F835 specifications for reliability.

Specification Summary & Compliance

This product features precise inch system measurements with a thread size of 5/16"-18 UNC and length of 3/4", adhering to Class 3A thread fit for tight tolerances. It complies with ASTM F835 for mechanical properties, RoHS 3 (2015/863/EU) for restricted hazardous substances, and REACH (EC 1907/2006) for chemical safety, ensuring suitability for industrial and export markets.