S-91255A058 5/8"-18 x 1" ASTM F835 Steel Button Head Hex-Drive Screws

Key Features & Benefits at a Glance

• Exceptional corrosion resistance with black-oxide coating, ideal for harsh industrial environments
• Superior torque transmission via 3/8" hex drive, preventing tool slippage and ensuring secure fastening
• High tensile strength of 120,000 psi for reliable performance under heavy loads and vibration
• Precise Class 3A thread fit ensuring tight tolerances and reduced risk of cross-threading in critical assemblies
• Fully threaded design providing maximum grip and load distribution along the entire 1" length
• Fine UNF threading (5/8"-18) offering better adjustment precision and vibration resistance compared to coarse threads
• Compliance with ASME B18.3 and ASTM F835 guaranteeing consistent quality and interchangeability

Professional Applications & Engineering Value

Engineered for demanding industrial applications, this Black-Oxide Alloy Steel Rounded Head Screw delivers outstanding durability in machinery, automotive, and heavy equipment assemblies. The fine UNF threading (5/8"-18) and Class 3A fit minimize loosening under vibration, while the 3/8" hex drive allows for high-torque installation without stripping. With a Rockwell C37 hardness and 120,000 psi tensile strength, it withstands extreme mechanical stress, making it ideal for structural fastening where reliability is critical. The fully threaded design ensures uniform stress distribution, reducing the risk of joint failure in high-load scenarios.

Specification Summary & Compliance

This screw features precise Class 3A thread fit per UNF standards, with a diameter of 0.625" and fine thread spacing. Manufactured in compliance with ASME B18.3 and ASTM F835 specifications, it meets stringent industrial requirements. The product is RoHS 3 (2015/863/EU) Compliant and REACH (EC 1907/2006) Compliant, ensuring environmental safety and regulatory adherence for global supply chains.