S-91375A117 4-48 x 5/16" ASME B18.3, ASTM F912 Set Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with Black-Oxide coating, extending service life in harsh environments
• Exceptional thread precision with Class 3A fit for reliable, vibration-resistant fastening in critical assemblies
• High-strength performance from Rockwell C45 hardened alloy steel, preventing deformation under load
• Space-saving headless design with 0.050" hex drive for flush installation in confined spaces
• Secure grip from cup point tip that bites into shafts, minimizing component slippage
• Fine UNF threading providing superior adjustment control and holding power
• Regulatory compliance meeting ASME B18.3, RoHS 3, and REACH for global industrial acceptance

Professional Applications & Engineering Value

This 4-48 UNF Class 3A set screw delivers engineering excellence for precision machinery and industrial equipment where space constraints and vibration resistance are critical. The Black-Oxide Alloy Steel construction provides superior corrosion protection while maintaining Rockwell C45 hardness for lasting performance. The headless hex drive design with 0.050" drive size enables flush mounting in tight tolerances, while the cup point tip creates permanent seating marks on shafts to prevent rotational slippage. Ideal for securing gears, pulleys, and collars in automotive, aerospace, and manufacturing applications where fine thread precision and reliable clamping force are essential for operational safety and reduced maintenance cycles.

Specification Summary & Compliance

Manufactured to exacting ASME B18.3 specifications with Class 3A thread fit for superior dimensional accuracy. Features 4-48 UNF fine threads with right-hand direction and 5/16" length. Fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, ensuring safe use across global industrial markets.