S-91375A448 5/8"-18 x 4" ASME B18.3, ASTM F912 Set Screws

Key Features & Benefits at a Glance

• Superior holding power with Class 3A thread fit for precise, vibration-resistant fastening in demanding applications
• Enhanced corrosion resistance from the black-oxide finish, extending service life in industrial environments
• Exceptional durability with Rockwell C45 hardness alloy steel construction, resisting wear and deformation
• Secure installation using the 5/16" hex drive, allowing high torque application without head interference
• Reliable grip from the cup tip design, preventing slippage and maintaining positional accuracy
• Industry-standard compatibility with 5/8"-18 UNF fine threads for precise component alignment
• Regulatory compliance assurance meeting ASME B18.3, RoHS 3, and REACH standards for global applications

Professional Applications & Engineering Value

This black-oxide alloy steel set screw delivers critical performance in precision machinery, automotive assemblies, and heavy equipment where vibration resistance and positional stability are paramount. The headless design with hex drive enables flush mounting in confined spaces while maintaining high torque capability. The Class 3A UNF fine threads provide superior engagement in tapped holes, minimizing loosening under dynamic loads. The cup tip configuration creates concentrated contact pressure, securely locking components against shafts and axles without damaging surfaces. Engineered for industrial set screw applications requiring repeatable accuracy and long-term reliability.

Specification Summary & Compliance

This 4" length set screw features 5/8"-18 UNF fine threads with Class 3A thread fit for precision tolerance. Manufactured to ASME B18.3 specifications with Rockwell C45 hardness alloy steel construction. Compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations. Right-hand thread direction with 0.625" thread diameter and 5/16" hex drive size.