S-91255A017 2-56 x 7/16" ASTM F835 Steel Button Head Hex-Drive Screws

Key Features & Benefits at a Glance

• Exceptional tensile strength of 120,000 psi ensures reliable performance under high-stress conditions, reducing the risk of fastener failure.
• Class 3A thread fit provides superior precision and tighter tolerances for secure, vibration-resistant connections in critical assemblies.
• Black-oxide coating on alloy steel enhances corrosion resistance and durability, extending service life in demanding industrial environments.
• Fully threaded design with coarse spacing allows for faster installation and improved grip in a variety of materials, boosting assembly efficiency.
• Hex drive (0.050") and rounded button head offer easy tool engagement and a low-profile finish, minimizing snagging and providing a clean appearance.
• Rockwell C39 hardness ensures high wear resistance, maintaining thread integrity through repeated use and disassembly.
• Compliance with ASME B18.3, ASTM F835, RoHS 3, and REACH guarantees adherence to industry standards and environmental regulations for safe, global use.

Professional Applications & Engineering Value

This 2-56 UNC rounded head hex drive screw is engineered to address common industrial challenges such as vibration loosening and material fatigue. The black-oxide alloy steel construction, combined with a Class 3A thread fit and coarse thread spacing, ensures a secure, durable fastening solution that withstands dynamic loads and harsh conditions. Ideal for precision assemblies in electronics, machinery, and automotive sectors, its fully threaded design and right-hand thread facilitate quick installation and reliable performance. The rounded button head and hex drive further enhance usability in confined spaces, making it a top choice for engineers seeking efficiency and longevity in industrial screw applications.

Specification Summary & Compliance

This screw features precise inch system dimensions including a 2-56 UNC thread size with Class 3A fit for tight tolerance control. It is manufactured in accordance with ASME B18.3 and ASTM F835 specifications, ensuring consistent quality and performance. 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.