S-90429A117 2-56 x 7/8" ASTM F835 Alloy Steel Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Exceptional tensile strength of 130,000 psi for reliable performance in high-stress applications, reducing the risk of fastener failure.
• Superior corrosion resistance from the black-oxide finish, extending service life in demanding industrial environments.
• Precise Class 3A thread fit ensures secure, vibration-resistant connections, minimizing loosening over time.
• Hex drive design provides easy installation with standard tools, speeding up assembly processes.
• 82° countersink angle allows for a flush, low-profile fit, enhancing aesthetics and safety in finished products.
• Partial threading offers optimal grip and clamping force, ideal for materials requiring controlled tension.
• Compliance with major standards including ASME B18.3 and ASTM F835, guaranteeing consistent quality and interchangeability.

Professional Applications & Engineering Value

These 2-56 UNC flat head screws are engineered from black-oxide alloy steel to address common industrial challenges such as corrosion, vibration loosening, and high mechanical stress. The coarse thread spacing and right-hand thread direction facilitate quick assembly in metals and plastics, while the Rockwell C39 hardness ensures durability against wear. Ideal for machinery, automotive components, and electronic enclosures, they provide a reliable fastening solution that maintains integrity under load, supported by a hex drive for efficient installation with standard wrenches.

Specification Summary & Compliance

This product adheres to Class 3A thread fit per UNC standards, ensuring precise dimensional accuracy. Manufacturing follows ASME B18.3 and ASTM F835 specifications for consistency. Compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming environmental safety and material restrictions are met.