S-91375A113 4-40 x 3/4" ASME B18.3, ASTM F912 Set Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with Black-Oxide coating on alloy steel, ideal for harsh industrial environments
• Exceptional holding power due to Rockwell C45 hardness, preventing loosening under vibration
• Precise installation and reliable fit with Class 3A thread tolerance for minimal backlash
• Easy tool engagement with 0.050" hex drive, allowing efficient assembly in confined spaces
• Secure component positioning using the cup tip design for concentrated contact pressure
• Broad compatibility with UNC coarse threads, suitable for various industrial assemblies
• Regulatory compliance assurance meeting ASME B18.3, RoHS 3, and REACH standards

Professional Applications & Engineering Value

This 4-40 UNC set screw delivers critical performance in precision machinery, automotive systems, and electronic enclosures where vibration resistance and positional accuracy are paramount. The Black-Oxide Alloy Steel construction provides enhanced durability against wear and environmental exposure, while the Class 3A thread fit ensures consistent clamping force without stripping. Its headless design with hex drive facilitates flush mounting in space-constrained applications, and the cup tip concentrates force to prevent shaft slippage. Engineered to ASME B18.3 specifications, it offers reliable performance for OEM and MRO requirements in demanding industrial settings.

Specification Summary & Compliance

This set screw adheres to UNC coarse thread standards with a Class 3A fit for precise dimensional accuracy. It conforms to ASME B18.3 manufacturing specifications and is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring environmental safety and material traceability.