S-91381A574 5/16"-18 x 1/4" ASME B18.3 Set Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with black-oxide coating, extending service life in harsh industrial environments
• Precise Class 3A thread fit ensures secure, vibration-resistant fastening with minimal backlash
• Non-marring brass tip protects sensitive components while maintaining strong clamping force
• High-strength alloy steel construction with Rockwell C28 hardness withstands heavy mechanical loads
• 5/32" hex drive design provides reliable torque transmission without head protrusion
• Coarse UNC threading enables quick installation and removal in time-sensitive operations
• Full regulatory compliance meets ASME B18.3 specifications and environmental standards (RoHS 3, REACH)

Professional Applications & Engineering Value

This black-oxide alloy steel set screw delivers exceptional performance in demanding industrial applications where component security and surface protection are critical. The Class 3A UNC thread system maintains precise tolerances for vibration-resistant fastening in machinery, automotive assemblies, and precision equipment. The soft brass tip eliminates damage to shafts, gears, and precision components while providing consistent clamping force. Engineered with Rockwell C28 hardness, this headless set screw resists deformation under heavy loads, making it ideal for permanent installations in manufacturing equipment, robotics, and power transmission systems where reliability cannot be compromised.

Specification Summary & Compliance

Manufactured to ASME B18.3 specifications with Class 3A thread fit for superior dimensional accuracy. Features 5/16"-18 UNC coarse threads with right-hand direction and 1/4" length. Full compliance with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations. The black-oxide surface treatment on alloy steel substrate provides corrosion protection while maintaining the Rockwell C28 hardness rating for long-term performance.