S-91255A708 1/2"-13 x 7/8" ASTM F835 Steel Button Head Hex-Drive Screws

Key Features & Benefits at a Glance

• Exceptional durability with 120,000 psi tensile strength and Rockwell C39 hardness for reliable performance in high-stress industrial applications
• Superior corrosion resistance from black-oxide coating that protects against rust and extends service life in demanding environments
• Secure fastening with Class 3A thread fit ensuring precise engagement and vibration resistance in critical assemblies
• Easy installation and removal with 5/16" hex drive design providing positive tool engagement and reduced stripping risk
• Full thread coverage along the 7/8" length for maximum grip strength and load distribution across connected components
• Industry-standard compliance meeting ASME B18.3 and ASTM F835 specifications for guaranteed interchangeability and quality
• Environmental responsibility with RoHS 3 and REACH compliance for safe use in regulated industries worldwide

Professional Applications & Engineering Value

These black-oxide alloy steel rounded head screws deliver critical performance advantages for industrial applications where high tensile strength and corrosion resistance are paramount. The UNC coarse thread spacing provides faster installation and superior resistance to vibration loosening in heavy machinery, construction equipment, and automotive assemblies. The button head profile offers a low-profile design that minimizes protrusion while the 5/16" hex drive ensures secure tool engagement during high-torque applications. Engineered with Class 3A thread fit, these screws maintain precise tolerances for reliable performance in critical joints subject to dynamic loads and thermal cycling, making them ideal for manufacturing, infrastructure, and mechanical systems requiring durable industrial fasteners.

Specification Summary & Compliance

This 1/2"-13 UNC screw features precision Class 3A thread fit with coarse spacing and full threading along its 7/8" length. Manufactured to exacting ASME B18.3 and ASTM F835 standards ensuring dimensional accuracy and mechanical properties. Fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations for restricted substance control. The black-oxide surface treatment provides additional corrosion protection while maintaining the alloy steel's inherent strength characteristics.