S-90429A267 1 1/4"-12 x 4 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 industrial applications, reducing the risk of fastener failure.
• Class 3A thread fit provides superior precision and tighter tolerances for secure, vibration-resistant assemblies in critical machinery.
• Alloy steel construction with Rockwell C37 hardness offers excellent durability and resistance to wear, extending service life in demanding environments.
• Partially threaded design with fine UNF threads allows for precise adjustment and strong clamping force, ideal for components requiring controlled tension.
• 82° countersink angle and flat head profile enable a flush, low-profile finish that minimizes protrusion and enhances safety in assembled structures.
• 7/8" hex drive facilitates easy installation and high torque application with standard tools, speeding up assembly processes.
• Compliance with ASTM F835, RoHS 3, and REACH ensures adherence to rigorous industry standards and environmental regulations, supporting sustainable procurement.

Professional Applications & Engineering Value

This alloy steel flat head screw is engineered to address common challenges in heavy-duty industrial settings, such as vibration loosening and material fatigue. The UNF fine thread and Class 3A fit provide enhanced grip and stability, making it ideal for precision equipment, automotive assemblies, and structural frameworks where high tensile strength and reliability are critical. The partially threaded design allows for focused stress distribution, reducing the risk of strip-out in softer materials. With an 82° countersink angle, it ensures a seamless fit in countersunk holes, preventing snagging and improving aerodynamic or aesthetic profiles in machinery and construction projects. These features collectively enhance assembly integrity, minimize maintenance needs, and support long-term operational efficiency in industrial screw applications.

Specification Summary & Compliance

This product meets precise dimensional standards, including a Class 3A thread fit for tight tolerances and UNF fine threading with a size of 1 1/4"-12. It is manufactured in accordance with ASTM F835 specifications, ensuring consistent quality and performance. Additionally, it is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming the absence of hazardous substances and supporting environmentally responsible sourcing for industrial use.