S-90484A535 1/4"-20 x 3/8" ASME B18.3, ASTM F835 Tamper-Resistant Hex-Drive Steel Button Head Screws

Key Features & Benefits at a Glance

• Enhanced tamper resistance with specialized hex drive requiring matching tools, preventing unauthorized removal in secure environments
• Superior corrosion protection through black-oxide coating on alloy steel, extending service life in demanding industrial conditions
• Exceptional load-bearing capacity with 130,000 psi tensile strength and Rockwell C39 hardness for heavy-duty applications
• Optimized thread engagement with Class 3A fit and UNC coarse spacing ensuring reliable fastening and vibration resistance
• Streamlined installation with rounded button head profile that eliminates sharp edges while providing attractive finish
• Maximum thread coverage through full threading along the 3/8" length for superior holding power in various material thicknesses
• Regulatory compliance assurance meeting multiple industry standards for quality and environmental safety

Professional Applications & Engineering Value

These black-oxide alloy steel screws with tamper-resistant hex drive address critical security and durability challenges in industrial settings. The rounded head design combines aesthetic appeal with practical safety, eliminating sharp protrusions in public-facing equipment while the 1/4-20 UNC coarse thread provides rapid installation and exceptional pull-out resistance. Engineered for high-stress applications requiring 130,000 psi tensile strength, these fasteners prevent tampering in security panels, access control systems, and public infrastructure. The black-oxide surface treatment offers reliable corrosion resistance without compromising dimensional accuracy, making them ideal for outdoor enclosures, machinery guards, and electronic housings where both security and environmental durability are paramount.

Specification Summary & Compliance

Manufactured to precise Class 3A thread fit standards with UNC coarse spacing for optimal engagement. These fully threaded screws feature a 5/32" tamper-resistant hex drive and comply with ASME B18.3 specifications where identified under ASTM F835. The product meets RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) compliance requirements, ensuring environmental safety and regulatory acceptance for industrial distribution and use.