S-91253A987 1 1/4"-7 x 5" 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 extreme loads, reducing the risk of fastener failure in demanding applications.
• Superior corrosion resistance from the black-oxide finish on alloy steel, extending service life in harsh industrial environments.
• Precise Class 3A thread fit provides tighter tolerances for secure, vibration-resistant assemblies, minimizing loosening over time.
• Fully threaded design offers consistent holding power along the entire 5" length, enhancing grip in thick materials.
• Optimized 82° countersink angle allows for a flush, low-profile installation, improving aesthetics and reducing snag hazards.
• Heavy-duty 7/8" hex drive enables high-torque installation with standard tools, speeding up assembly while preventing stripping.
• Compliance with RoHS 3 and REACH ensures environmental and safety standards are met, supporting responsible sourcing and usage.

Professional Applications & Engineering Value

Engineered for heavy-duty industrial applications, these 1 1/4"-7 UNC flat head screws address critical challenges in machinery, construction, and structural assemblies. The black-oxide alloy steel construction, combined with a Rockwell C37 hardness, provides exceptional resistance to wear and environmental factors, reducing maintenance needs. The coarse thread spacing and fully threaded profile ensure rapid installation and robust clamping force in materials like steel or thick composites, preventing joint failure under dynamic loads. Ideal for use in high-stress environments where corrosion resistance and long-term reliability are paramount, these screws deliver consistent performance while meeting stringent ASTM F835 specifications.

Specification Summary & Compliance

This screw adheres to Class 3A thread fit for precise engagement and UNC coarse threading (1 1/4"-7) to facilitate quick assembly. Dimensions include a 5" length, 2.438" head diameter, and 0.683" head height, with an 82° countersink angle for standard flush mounting. It conforms to ASTM F835 manufacturing standards and is verified as RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) compliant, ensuring adherence to international safety and environmental regulations.