S-91221A216 4-40 x 3/8" UL 94 HB Plastic Socket Head Screws
Plastic Socket Head Screws
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Basic Information
Head Parameters
Dimensions
Thread Parameters
Tip & Drive Parameters
Material & Strength
Temperature & Environment
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Key Features & Benefits at a Glance
- Enhanced durability and strength with glass-filled nylon construction, providing reliable performance in demanding industrial environments
- Wide temperature resistance from -20° to 230°F, ensuring stability in varied operating conditions without degradation
- Secure and precise fastening with UNC coarse threading and Class 2A fit, reducing cross-threading risks and improving assembly efficiency
- Easy installation and removal using a standard 3/32" hex drive, compatible with common tools for quick maintenance
- Flame retardant safety meeting UL 94 HB standards, ideal for applications requiring reduced flammability
- Environmental compliance with RoHS 3 and REACH regulations, supporting sustainable and safe manufacturing practices
- Corrosion-resistant and lightweight off-white plastic design, perfect for electrical and non-magnetic applications
Professional Applications & Engineering Value
This 4-40 UNC glass-filled nylon socket head cap screw delivers exceptional engineering value by addressing common industrial challenges like corrosion, weight, and electrical conductivity. The glass-filled nylon material offers high tensile strength and dimensional stability, preventing stripping or failure under stress. With a right-hand coarse thread and Class 2A fit, it ensures quick, secure fastening in plastics, composites, or lightweight metals, reducing assembly time and errors. Ideal for electrical enclosures, automotive components, and machinery, its temperature resistance and UL 94 HB certification make it suitable for environments where flame retardancy and durability are critical, while the hex drive allows for tight spaces and reliable torque application.
Specification Summary & Compliance
This screw features precise 4-40 UNC coarse threads with a Class 2A fit for standard tolerance and easy assembly. It complies with UL 94 HB for flammability safety, RoHS 3 (2015/863/EU) for hazardous substance restrictions, and REACH (EC 1907/2006) for chemical management, ensuring regulatory adherence in industrial and electronic applications.
