S-91221A168 1/4"-20 x 3/8" UL 94 HB Plastic Socket Head Screws

Key Features & Benefits at a Glance

• Enhanced Durability & Lightweight Design: Glass-filled nylon construction offers superior strength-to-weight ratio, reducing component fatigue and improving longevity in demanding environments.
• Wide Temperature Resistance: Operates reliably from -20°F to 230°F, ensuring stable performance in fluctuating industrial conditions without compromising integrity.
• Precision UNC Coarse Threads with Class 2A Fit: Facilitates quick, secure assembly and reduces cross-threading risks, enhancing installation efficiency and joint reliability.
• Hex Socket Drive for High Torque Application: 3/16" hex drive allows for tight, flush installations in confined spaces, minimizing strip-out and improving fastener accessibility.
• Compliance with Safety & Environmental Standards: UL 94 HB flammability rating, RoHS 3, and REACH compliance ensure safety, regulatory adherence, and suitability for eco-conscious industries.
• Corrosion & Chemical Resistance: Off-white nylon material inherently resists moisture, chemicals, and electrical insulation, ideal for harsh or sensitive applications.
• Fully Threaded Design for Maximum Grip: Ensures consistent clamping force along the entire 3/8" length, providing secure fastening in varied material thicknesses.

Professional Applications & Engineering Value

Engineered for precision and resilience, this glass-filled nylon socket head cap screw addresses common industrial challenges such as corrosion, weight reduction, and electrical isolation. The UNC coarse thread with Class 2A fit enables rapid assembly in plastics, composites, and metals, reducing installation time while maintaining vibration resistance. Its temperature range of -20° to 230° F makes it suitable for automotive, electronics, and outdoor equipment, where thermal stability is critical. The hex drive design ensures high torque capability without protruding heads, ideal for streamlined assemblies in machinery, enclosures, and consumer goods requiring UL 94 HB rated safety and RoHS/REACH compliance.

Specification Summary & Compliance

This screw adheres to UNC thread standards with a Class 2A thread fit for consistent dimensional accuracy. It meets UL 94 HB flammability specifications, ensuring reduced fire hazard in plastic components. Compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, it is free of restricted substances, supporting sustainable manufacturing practices. Fully threaded and right-hand oriented, it is manufactured for reliable performance in industrial plastic fastener applications.