S-91385A576 5/16"-18 x 3/8" ASME B18.3, ASTM F912 Set Screws

Key Features & Benefits at a Glance

• Vibration-resistant locking with nylon patch thread locker that maintains secure fastening from -50°F to 250°F
• Superior corrosion protection through black-oxide finish on alloy steel construction
• Precise thread engagement with Class 3A fit UNC coarse threads for reliable holding power
• High-strength durability with Rockwell C45 hardness for heavy-duty industrial applications
• Space-saving headless design with hex drive for flush mounting in confined spaces
• Enhanced grip performance through cup tip design that concentrates pressure on contact surface
• Industry-standard compliance meeting ASME B18.3 specifications for quality assurance

Professional Applications & Engineering Value

This black-oxide alloy steel set screw delivers exceptional vibration resistance in demanding industrial environments where secure locking is critical. The nylon patch thread locker embedded in the UNC coarse threads prevents loosening under extreme conditions, maintaining clamping force from -50°F to 250°F. The headless hex drive design allows for flush installation in pulleys, gears, and collars where protruding fastener heads are impractical. With Rockwell C45 hardness and cup tip configuration, this set screw provides concentrated contact pressure for superior grip on shafts and rotating components, making it ideal for machinery, automotive, and manufacturing applications requiring reliable positioning and torque transmission.

Specification Summary & Compliance

This set screw features precision UNC 5/16"-18 threads with Class 3A fit tolerance for optimal engagement. Manufactured to ASME B18.3 specifications (ASTM F912) with Rockwell C45 hardness rating. The product is fully RoHS 3 (2015/863/EU) Compliant and REACH (EC 1907/2006) Compliant, meeting international environmental and safety standards for industrial use.