S-91221A183 1/4"-20 x 5/8" UL 94 HB Plastic Socket Head Screws

Key Features & Benefits at a Glance

• Exceptional durability with glass-filled nylon construction that resists corrosion and provides reliable performance in demanding environments.
• Wide temperature tolerance from -20°F to 230°F, ensuring stability in varied operational conditions without degradation.
• Secure hex drive engagement with a 3/16" hex drive for precise torque application and reduced risk of stripping during installation.
• Consistent thread performance thanks to UNC coarse threads and Class 2A fit, enabling quick assembly and strong holding power.
• Electrical insulation properties ideal for applications requiring non-conductive fasteners to prevent short circuits.
• Compliance with industry standards including UL 94 HB for flammability, RoHS 3, and REACH, ensuring safety and environmental responsibility.
• Fully threaded design for maximum grip and adjustability across the entire 5/8" length in various materials.

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 thermal expansion. The black glass-filled nylon plastic material offers excellent strength-to-weight ratio and resists chemicals, making it suitable for electrical enclosures, automotive components, and machinery where metal fasteners could cause galvanic corrosion or interference. Its UNC coarse threads and Class 2A thread fit ensure easy alignment and reduced cross-threading in assemblies, while the hex drive allows for high-torque applications without slippage. Ideal for industrial plastic fasteners in environments requiring corrosion resistance and electrical insulation, this screw enhances assembly longevity and safety in temperature-fluctuating settings.

Specification Summary & Compliance

This screw adheres to precise dimensional standards, including UNC thread type with Class 2A thread fit for consistent accuracy and ease of use. It meets UL 94 HB for flammability resistance, RoHS 3 (2015/863/EU) for restricted hazardous substances, and REACH (EC 1907/2006) compliance, ensuring it aligns with global environmental and safety regulations for industrial applications.