S-91221A139 6-32 x 1/2" ASME B18.3, UL 94 HB Plastic Socket Head Screws

Key Features & Benefits at a Glance

• Exceptional corrosion resistance due to glass-filled nylon construction, ideal for harsh environments without risk of rust or degradation.
• High tensile strength of 17,000 psi ensures reliable fastening under mechanical stress, reducing the risk of failure in critical assemblies.
• Broad temperature tolerance from -40° to 200°F maintains performance in both extreme cold and moderate heat applications.
• Lightweight and non-conductive properties make it perfect for electrical and weight-sensitive assemblies where metal fasteners are unsuitable.
• Hex socket drive (7/64") allows for secure, high-torque installation with standard tools, minimizing stripping and improving assembly efficiency.
• Class 2A thread fit with 6-32 UNC coarse threads provides easy engagement and consistent clamping force, reducing cross-threading risks.
• Compliance with ASME B18.3, UL 94 HB, RoHS 3, and REACH ensures adherence to industry standards for safety, environmental responsibility, and quality.

Professional Applications & Engineering Value

This glass-filled nylon socket head cap screw is engineered to address common industrial challenges such as corrosion, electrical conductivity, and weight constraints. The black plastic screw with 6-32 UNC coarse threads offers excellent chemical resistance, making it suitable for applications in electronics, automotive, and marine environments where metal fasteners would corrode or cause galvanic reactions. Its fully threaded design ensures uniform load distribution, while the hex drive style enables precise installation in confined spaces. By combining high tensile strength with a wide temperature range, this fastener provides long-term reliability in assemblies exposed to thermal cycling and mechanical vibrations, reducing maintenance needs and enhancing product lifespan.

Specification Summary & Compliance

The screw features precise Class 2A thread fit per UNC standards, ensuring dimensional accuracy and compatibility with standard nuts and threaded holes. Manufactured in accordance with ASME B18.3 specifications, it also meets UL 94 HB for flammability resistance, RoHS 3 (2015/863/EU) for restricted substance compliance, and REACH (EC 1907/2006) regulations, affirming its suitability for global industrial and commercial use without environmental or health concerns.