S-91375A102 4-40 x 3/32" ASME B18.3, ASTM F912 Set Screws

Key Features & Benefits at a Glance

• Maximum holding power with Class 3A thread fit for secure, vibration-resistant fastening in demanding applications
• Superior corrosion resistance from black-oxide coating on alloy steel, extending service life in harsh industrial environments
• High-strength durability with Rockwell C45 hardness, maintaining structural integrity under heavy loads and repeated use
• Precise installation control through 0.050" hex drive, allowing accurate torque application in confined spaces
• Reliable thread engagement with UNC coarse threads, enabling quick assembly and reduced cross-threading risks
• Secure component positioning using cup tip design that creates positive locking contact on shaft surfaces
• Industry-standard compliance meeting ASME B18.3 specifications for consistent performance and interchangeability

Professional Applications & Engineering Value

This 4-40 UNC set screw delivers exceptional engineering value in precision assembly applications where space constraints and vibration resistance are critical concerns. The black-oxide alloy steel construction provides superior corrosion protection while maintaining the Rockwell C45 hardness necessary for high-stress environments. The headless design with hex drive allows installation in confined spaces where traditional fastener heads would interfere, while the cup tip ensures positive locking on shafts and components in machinery, automotive systems, and electronic enclosures. The Class 3A thread fit guarantees precise tolerances for maximum clamping force, making these set screws ideal for permanent fastening applications requiring reliable, long-term performance without maintenance.

Specification Summary & Compliance

This precision fastener features 4-40 UNC coarse threads with Class 3A thread fit for superior dimensional accuracy and holding power. Manufactured to ASME B18.3 specifications, the set screw ensures consistent performance and interchangeability. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, meeting the latest industry standards for hazardous substance restrictions. With a length of 3/32" and 0.050" hex drive, this fastener delivers precise installation and reliable performance in industrial applications.