S-91255A036 5/16"-18 x 2 3/4" ASTM F835 Steel Button Head Hex-Drive Screws

Key Features & Benefits at a Glance

• Exceptional corrosion resistance with Black-Oxide finish, ideal for harsh industrial environments.
• High tensile strength of 120,000 psi ensures reliable performance in demanding applications.
• Precise Class 3A thread fit provides superior engagement and vibration resistance.
• Fully threaded design allows for maximum grip and load distribution along the entire length.
• Hex drive with 3/16" size offers secure, slip-resistant installation with common tools.
• Hardened to Rockwell C39 for excellent durability and wear resistance.
• Compliant with ASME B18.3 and ASTM F835, ensuring consistent quality and interchangeability.

Professional Applications & Engineering Value

This Black-Oxide Alloy Steel Rounded Head Screw is engineered to address critical industrial challenges, such as vibration loosening and environmental degradation. The UNC coarse thread and Class 3A fit deliver superior holding power in metals and plastics, minimizing the risk of assembly failure. Its fully threaded 2 3/4" length ensures maximum engagement in thick materials, while the button head style provides a low-profile, flush finish for safety and aesthetics. Ideal for machinery, automotive, and heavy equipment applications, this screw combines high tensile strength and corrosion resistance to extend service life and reduce maintenance costs in rigorous conditions.

Specification Summary & Compliance

This screw features a 5/16"-18 UNC coarse thread with Class 3A precision fit for tight tolerances. It is manufactured in accordance with ASME B18.3 and ASTM F835 standards, ensuring dimensional accuracy and performance reliability. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, supporting environmentally responsible sourcing and use in global markets.