S-91385A356 5/16"-24 x 5/16" ASME B18.3, ASTM F912 Set Screws

Key Features & Benefits at a Glance

• Permanent vibration resistance through integrated nylon patch thread locking, ensuring secure fastening in high-motion applications
• Exceptional temperature tolerance from -50°F to 250°F, maintaining locking integrity in extreme thermal environments
• Superior wear and corrosion resistance with black-oxide alloy steel construction and Rockwell C45 hardness for extended service life
• Precise Class 3A thread fit for tighter tolerances and reliable engagement in critical assemblies
• Secure installation and removal with 5/32" hex drive design, providing optimal torque transmission in confined spaces
• Effective grip and positioning with cup point tip that bites into mating surfaces to prevent component slippage
• Regulatory compliance assurance meeting ASME B18.3, RoHS 3, and REACH standards for global industrial applications

Professional Applications & Engineering Value

This 5/16"-24 UNF Class 3A set screw delivers critical engineering solutions for demanding industrial environments where vibration-induced loosening compromises assembly integrity. The nylon patch locking technology creates permanent friction resistance without requiring separate locking components, streamlining installation while providing reliable performance across temperature extremes from -50°F to 250°F. Manufactured from black-oxide alloy steel with Rockwell C45 hardness, these headless set screws offer superior strength and corrosion resistance for permanent positioning applications in machinery, automotive systems, and precision equipment. The fine UNF threads with Class 3A fit ensure precise engagement in threaded holes, while the cup point design provides maximum gripping force to prevent rotational movement of components on shafts and collars.

Specification Summary & Compliance

This precision fastener features 5/16"-24 UNF fine threads with Class 3A thread fit for superior dimensional accuracy and engagement. Manufacturing complies with ASME B18.3 specifications (ASTM F912) ensuring consistent quality and performance. The product meets RoHS 3 (2015/863/EU) compliance for restricted substance control and REACH (EC 1907/2006) compliance for chemical safety regulations. The nylon patch thread locker provides permanent locking capability without compromising the Rockwell C45 hardness of the base black-oxide alloy steel material.