S-91979A311 4-40 x 1/4" Set Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 18-8 stainless steel construction for long-lasting performance in harsh industrial environments
• Exceptional holding power achieved through Class 3A thread fit, ensuring tight, secure fastening in precision applications
• Easy installation and removal with hex drive design (0.050" drive size) providing reliable torque transmission
• Enhanced ventilation capability through vented tip design (0.035" vent diameter) preventing pressure buildup during installation
• Optimized for right-hand applications with coarse UNC thread spacing for quick assembly and disassembly
• Space-saving headless design allowing for flush mounting in confined spaces and rotating assemblies
• Regulatory compliance assurance meeting RoHS 3 and REACH standards for safe use across various industries

Professional Applications & Engineering Value

This 4-40 UNC thread set screw delivers exceptional engineering value in precision fastening applications where reliability is paramount. The 18-8 stainless steel construction provides excellent corrosion resistance, making it ideal for machinery, electronic enclosures, and automotive components exposed to moisture or chemicals. The hex drive design with 0.050" drive size ensures secure torque application without slippage, while the vented tip prevents air pressure buildup during installation, reducing the risk of component damage. The Class 3A thread fit guarantees precise engagement with mating parts, maintaining positional accuracy in assemblies requiring repeated adjustments. These headless set screws with cup tip configuration are particularly valuable in securing collars, pulleys, and gears on shafts where protruding fasteners would interfere with operation.

Specification Summary & Compliance

This precision fastener features 4-40 UNC coarse threads with Class 3A thread fit for superior dimensional accuracy and holding capability. The right-hand thread direction and 1/4" length provide standardized compatibility across industrial applications. Manufactured to exacting standards, this set screw maintains compliance with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring environmental safety and material transparency. The combination of precise thread specifications and regulatory adherence makes this fastener suitable for demanding industrial environments requiring both technical performance and compliance assurance.