S-90291A105 4-40 ASME B18.3 Set Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 18-8 stainless steel construction, ideal for harsh industrial environments
• Precise thread engagement with Class 3A fit for reliable, vibration-resistant fastening in critical assemblies
• Secure component protection from the non-marring green nylon 6/6 tip, preventing surface damage
• Wide temperature tolerance with nylon tip rated for -50° to 250°F, ensuring performance in varied conditions
• High durability backed by Rockwell B80 hardness for long-term mechanical integrity
• Easy installation and removal using the compact .050" hex drive in confined spaces
• Regulatory compliance with ASME B18.3, RoHS 3, and REACH for safe, industry-approved use

Professional Applications & Engineering Value

This 4-40 UNC set screw is engineered to address common industrial challenges like component slippage and surface damage in precision equipment. The 18-8 stainless steel body offers excellent corrosion resistance, while the Class 3A thread fit ensures tight, reliable fastening that resists loosening under vibration. The nylon 6/6 plastic tip provides a soft, non-abrasive contact point, protecting sensitive parts from scratches or deformation. Ideal for applications in electronics, machinery, and automotive assemblies, this headless set screw with coarse thread spacing delivers consistent clamping force and easy adjustment in space-constrained environments, enhancing overall assembly longevity and performance.

Specification Summary & Compliance

This set screw features a 4-40 UNC thread with Class 3A precision fit for accurate thread engagement. It meets ASME B18.3 manufacturing standards and is compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring environmental safety and material reliability.