S-91870A755 1/4"-20 x 1 1/2" ASME B18.3 Tamper-Resistant Torx Stainless Steel Flat Head Screws

Key Features & Benefits at a Glance

• Enhanced tamper resistance with Torx Plus IPR30 drive prevents unauthorized access, ideal for security-critical installations
• Superior corrosion resistance from 18-8 stainless steel construction and passivated finish ensures long-term reliability in harsh environments
• High-strength performance with 70,000 psi tensile strength and Rockwell B70 hardness withstands heavy-duty mechanical stress
• Precise thread engagement via Class 3A UNC coarse threading provides secure, vibration-resistant fastening in industrial applications
• Flush mounting capability with standard 82° flat head profile allows for smooth surface finishes in assembled products
• Full regulatory compliance with ASME B18.3, RoHS 3, and REACH ensures safety and environmental standards are met
• Versatile 1-1/2" length with full threading offers flexible fastening depth for various material thicknesses

Professional Applications & Engineering Value

Engineered for high-security industrial applications, this 18-8 stainless steel flat head screw addresses critical challenges in public infrastructure, machinery guarding, and electronic enclosures where tampering poses operational risks. The Tamper-Resistant Torx Plus IPR30 drive requires specialized tools, deterring unauthorized disassembly while maintaining installation efficiency for maintenance crews. Its passivated finish enhances the natural corrosion resistance of stainless steel, making it suitable for outdoor installations, marine-adjacent equipment, and chemical processing facilities where moisture and corrosive agents degrade ordinary fasteners. Combined with Class 3A UNC coarse threading, the screw delivers reliable clamp load distribution in metals, plastics, and composite materials—preventing loosening under vibration in conveyor systems, HVAC assemblies, and transportation equipment.

Specification Summary & Compliance

This fastener maintains Class 3A thread fit per unified inch standards, ensuring precise dimensional accuracy for consistent engagement. Manufacturing adheres to ASME B18.3 specifications for flat head geometry and mechanical properties. The screw is fully RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) compliant, confirming absence of restricted hazardous substances. Threading follows UNC 1/4"-20 coarse spacing with full threading along the 1-1/2" length, supporting standardized installation practices across industrial sectors.