S-91375A107 4-40 x 5/16" ASME B18.3, ASTM F912 Set Screws

Key Features & Benefits at a Glance

• Superior holding power with Class 3A thread fit ensuring tight, secure connections in demanding applications
• Exceptional durability from Black-Oxide Alloy Steel construction providing reliable corrosion resistance and extended service life
• High-strength performance backed by Rockwell C45 hardness for maintaining integrity under heavy loads and vibration
• Secure installation with hex drive design allowing precise torque application and preventing tool slippage
• Enhanced grip capability through cup tip design that digs into surfaces for superior anti-loosening performance
• Industry-standard compatibility with UNC coarse threads ensuring easy installation and broad application suitability
• Space-saving design as a headless set screw ideal for confined spaces and flush mounting requirements

Professional Applications & Engineering Value

This 4-40 UNC set screw delivers exceptional engineering value in industrial fastening applications where vibration resistance and secure positioning are critical. The Black-Oxide Alloy Steel construction combined with Rockwell C45 hardness ensures reliable performance in machinery, automotive components, and precision equipment. The headless hex drive design allows for flush mounting in tight spaces while providing superior torque transmission. The cup tip configuration creates positive engagement with mating surfaces, preventing component slippage in high-vibration environments. These industrial set screws are particularly valuable in assembly lines, manufacturing equipment, and precision instruments where Class 3A thread fit guarantees consistent, repeatable performance and reduced maintenance requirements.

Specification Summary & Compliance

This set screw maintains precise Class 3A thread fit tolerances with 4-40 UNC coarse threads and right-hand thread direction. Manufactured to ASME B18.3 specifications (ASTM F912) with a length of 5/16" and 0.050" hex drive size. The product is fully compliant with RoHS 3 (2015/863/EU) environmental standards and REACH (EC 1907/2006) regulations, ensuring safe use across various industrial sectors while meeting international quality and safety requirements.