S-90251A168 4-40 x 3/16" ASME B18.3 Set Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 316 Stainless Steel construction for reliable performance in harsh environments
• Exceptional vibration resistance through Nylon Patch thread locker that maintains secure fastening from -50° to 250°F
• Precise thread engagement with Class 3A thread fit ensuring maximum holding power and reduced loosening
• Space-saving headless design with hex drive allowing flush mounting in confined applications
• Enhanced torque transmission through 0.050" hex drive providing secure installation without stripping
• Optimized material strength with Rockwell B80 hardness balancing durability and machinability
• Reliable regulatory compliance meeting ASME B18.3 standards and environmental regulations (RoHS 3, REACH)

Professional Applications & Engineering Value

This 4-40 UNC set screw in 316 Stainless Steel delivers critical performance advantages for precision assembly applications. The hex headless design with Class 3A thread fit provides exceptional clamping force while maintaining minimal profile in space-constrained machinery. The integrated Nylon Patch thread locker effectively counters vibration-induced loosening across extreme temperature ranges (-50° to 250°F), making it ideal for automotive, aerospace, and industrial equipment where thermal cycling is common. The coarse thread spacing and cup tip design ensure positive engagement with mating components, while the corrosion-resistant properties of 316 stainless steel protect against chemical exposure and moisture in demanding environments.

Specification Summary & Compliance

This set screw features precision 4-40 UNC threads with Class 3A thread fit for superior dimensional accuracy. Manufactured to ASME B18.3 specifications, the fastener ensures consistent performance and interchangeability. The product maintains full compliance with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, confirming its suitability for global industrial applications. Additional specifications include right-hand thread direction, 3/16" length, and Rockwell B80 hardness for optimal mechanical properties.