S-90291A537 1/4"-20 ASME B18.3 Set Screws

Key Features & Benefits at a Glance

• Superior vibration resistance with the nylon 6/6 plastic tip that prevents loosening under dynamic loads and protects mating surfaces from damage
• Exceptional corrosion resistance from 18-8 stainless steel construction, ideal for harsh or washdown environments
• Precise, secure fastening ensured by the Class 3A thread fit for tighter tolerances and reliable holding power
• High-strength performance with a Rockwell B80 hardness rating, providing excellent durability and resistance to wear
• Wide temperature compatibility as the nylon tip operates reliably from -50° to 250° F, suitable for varied industrial conditions
• Easy, high-torque installation using the 1/8" hex drive, allowing for efficient assembly with standard tools
• Safe and regulated use with compliance to RoHS 3 and REACH environmental standards, ensuring material safety

Professional Applications & Engineering Value

This 1/4"-20 UNC Class 3A hex drive set screw is engineered to solve critical fastening challenges in industrial settings. The 18-8 stainless steel material offers excellent resistance to corrosion and oxidation, making it ideal for applications in machinery, automotive, and outdoor equipment where exposure to moisture and chemicals is common. The coarse UNC thread and Class 3A fit provide superior grip and minimal backlash, essential for maintaining alignment in assemblies subject to vibration. The green nylon 6/6 plastic tip not only prevents marring of shafts and gears but also dampens vibrations, reducing the risk of unintended loosening in high-stress environments. By meeting ASME B18.3 specifications, this headless set screw delivers consistent performance for precise mounting and positioning tasks, enhancing the longevity and reliability of your equipment.

Specification Summary & Compliance

This set screw adheres to strict dimensional and performance standards, including 1/4"-20 UNC coarse threads with a Class 3A thread fit for high precision. It is manufactured in compliance with ASME B18.3 and meets environmental regulations such as RoHS 3 (2015/863/EU) and REACH (EC 1907/2006), ensuring it is free from hazardous substances. The Rockwell B80 hardness and specified temperature range further confirm its suitability for demanding industrial applications.