S-91385A366 3/8"-24 x 1/2" ASME B18.3, ASTM F912 Set Screws

Key Features & Benefits at a Glance

• Vibration-resistant locking with nylon patch thread locker maintains secure fastening in high-stress environments
• Superior corrosion protection from black-oxide coating extends service life in demanding industrial conditions
• Precision thread engagement with Class 3A UNF fine threads ensures reliable, zero-backlash connections
• Exceptional mechanical strength from Rockwell C45 hardened alloy steel prevents stripping and deformation
• Wide temperature tolerance (-50°F to 250°F) maintains locking performance across extreme operating conditions
• Space-saving headless design with hex drive allows installation in confined spaces while providing positive torque transmission
• Regulatory compliance assurance meets ASME B18.3, ASTM F912, RoHS 3, and REACH standards for global industrial applications

Professional Applications & Engineering Value

This black-oxide alloy steel set screw delivers critical vibration resistance in machinery, automotive, and aerospace assemblies where UNF fine threads and Class 3A precision fit prevent loosening under dynamic loads. The nylon patch locking technology creates consistent friction that eliminates the need for secondary locking devices, while the cup tip design provides positive seating on shafts and collars. Engineered for high-temperature environments up to 250°F, this headless set screw with hex drive installation solves space-constrained fastening challenges while maintaining Rockwell C45 hardness for repeated adjustment cycles without thread degradation.

Specification Summary & Compliance

Manufactured to ASME B18.3 and ASTM F912 specifications with Class 3A thread fit for precision UNF fine threading (3/8"-24). Features include: 1/2" length, 3/16" hex drive, cup tip configuration, and black-oxide surface treatment. Full compliance with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations for industrial use.