S-91375A121 5-40 x 1/8" ASME B18.3, ASTM F912 Set Screws
Set Screws
Image may differ from product. See technical specification for details.
Basic Information
Head Parameters
Dimensions
Thread Parameters
Tip & Drive Parameters
Material & Strength
Temperature & Environment
- Fast delivery
- Enjoy discounts on bulk purchases
- Secure Payment
- Fast Global Shipping
Key Features & Benefits at a Glance
- Superior corrosion resistance with Black-Oxide Alloy Steel construction, extending service life in harsh environments
- Precise thread engagement with Class 3A thread fit ensuring reliable, vibration-resistant fastening in critical assemblies
- High durability under load thanks to Rockwell C45 hardness, maintaining structural integrity in demanding applications
- Secure installation and removal with 1/16" hex drive, providing excellent torque transmission without head protrusion
- Effective component positioning using cup tip design for concentrated contact pressure and minimal surface damage
- Wide compatibility with coarse UNC threads and right-hand direction, suitable for standard industrial equipment
- Regulatory peace of mind through compliance with ASME B18.3, RoHS 3, and REACH for global market acceptance
Professional Applications & Engineering Value
This 5-40 UNC set screw delivers exceptional engineering value in precision assemblies where space constraints and reliability are paramount. The headless design and compact 1/8" length allow flush mounting in tight spaces, while the Black-Oxide surface treatment on alloy steel provides a protective barrier against oxidation and mild chemical exposure. Its Class 3A thread fit and coarse UNC thread form ensure consistent clamping force in vibrating machinery, preventing loosening in motor couplings, gear assemblies, and precision instruments. The cup tip concentrates force on shafts and collars without excessive marring, making it ideal for permanent positioning applications in automotive, aerospace, and industrial automation sectors where repeatable accuracy is critical.
Specification Summary & Compliance
This set screw maintains precise Class 3A thread tolerances per UNC standards with a thread diameter of 0.125" and coarse thread spacing. Manufacturing follows ASME B18.3 specifications (ASTM F912) for dimensional consistency. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring environmental safety and unrestricted use in international markets.
