S-99477A104 4-40 x 3/16" ASME B18.3, UL 94 HB Plastic Socket Head Screws

Key Features & Benefits at a Glance

• Exceptional chemical resistance from polypropylene plastic construction, ideal for corrosive environments
• Reliable 4500 psi tensile strength provides secure fastening for industrial assemblies
• Broad temperature tolerance (-20° to 180°F) maintains performance across diverse operating conditions
• Precision Class 2A thread fit ensures smooth installation and consistent engagement
• Standard hex drive compatibility with 3/32" tools enables quick installation and removal
• Coarse UNC threading delivers superior holding power in plastic and soft materials
• Comprehensive regulatory compliance meets ASME B18.3, RoHS 3, and REACH standards

Professional Applications & Engineering Value

These 4-40 UNC socket head cap screws deliver exceptional value in applications where metal fasteners would corrode or conduct electricity. The polypropylene plastic construction provides inherent resistance to chemicals, moisture, and electrical isolation, making them perfect for electrical enclosures, laboratory equipment, and food processing machinery. The coarse thread design ensures maximum holding power in plastic components and soft materials, while the standard hex drive allows for efficient installation in confined spaces. With operating temperatures from -20° to 180°F, these industrial plastic fasteners maintain dimensional stability across demanding environments, solving corrosion and conductivity concerns while providing reliable mechanical performance.

Specification Summary & Compliance

These socket head cap screws feature precision Class 2A thread fit with 4-40 UNC coarse threading and right-hand thread direction. Manufactured to ASME B18.3 specifications with 3/16" length and 3/32" hex drive. Fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring environmental safety and regulatory adherence for global industrial applications.