S-91375A544 1/4"-20 x 1 1/4" ASME B18.3, ASTM F912 Set Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with black-oxide coating for extended service life in harsh industrial environments
• Maximum thread engagement reliability through Class 3A fit for vibration-resistant assemblies
• Exceptional hardness rating (Rockwell C45) prevents deformation under high torque applications
• Secure tamper-resistant fastening with headless design and 1/8" hex drive requiring specialized tools
• Positive locking action from cup point tip that bites into shafts for permanent positioning
• Quick installation with coarse UNC threads reducing assembly time in production environments
• Regulatory compliance assurance meeting global standards for material safety and engineering specifications

Professional Applications & Engineering Value

This black-oxide alloy steel set screw delivers critical performance in demanding applications where vibration resistance and permanent positioning are paramount. The Class 3A thread fit maintains precise tolerances in machinery components, while the cup point design creates permanent dimples in shafts for superior anti-rotation security. Engineered with Rockwell C45 hardness, it withstands repeated adjustments without thread deformation. The corrosion-resistant black-oxide finish protects against industrial atmospheres, making it ideal for power transmission systems, gear assemblies, and precision manufacturing equipment where reliability cannot be compromised.

Specification Summary & Compliance

Manufactured to ASME B18.3 specifications with 1/4"-20 UNC Class 3A coarse threads ensuring dimensional accuracy. Complies with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations. Features right-hand thread direction with 1-1/4" length and 1/8" hex drive for standardized tool compatibility across industrial maintenance and assembly operations.