S-91770A895 1/4"-28 x 1 1/4" ASME B18.6.3 Stainless Steel Truss Head Phillips Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with passivated 18-8 stainless steel construction for extended service life in harsh environments
• Exceptional mechanical strength with 70,000 psi tensile strength and Rockwell B70 hardness to withstand heavy loads and vibration
• Enhanced load distribution from the wide truss head design that reduces surface pressure and prevents material damage
• Precise thread engagement with Class 2A fit and UNF fine threads ensuring secure, vibration-resistant fastening
• Optimized installation efficiency through Phillips No. 3 drive compatibility with common industrial tools
• Full-threaded design providing maximum grip length and uniform stress distribution along the entire fastener
• Regulatory compliance assurance meeting ASME B18.6.3, RoHS 3, and REACH standards for global industrial applications

Professional Applications & Engineering Value

Engineered for demanding industrial environments, these 1/4-28 UNF rounded truss head screws deliver critical performance advantages where reliability is non-negotiable. The passivated 18-8 stainless steel construction provides exceptional resistance to corrosion, oxidation, and chemical exposure, making them ideal for outdoor equipment, marine applications, and chemical processing facilities. The unique truss head profile offers significantly larger bearing surface than standard heads, distributing clamp load over wider areas to prevent damage to soft materials and composite surfaces. Combined with fine thread spacing and Class 2A thread fit, these fasteners maintain secure connections in high-vibration machinery, automotive assemblies, and precision equipment where loosening could cause catastrophic failure. The fully threaded design ensures maximum engagement in both thick and thin materials, providing versatile application across diverse industrial fastening requirements.

Specification Summary & Compliance

These industrial-grade fasteners feature precision 1/4"-28 UNF threads with Class 2A fit tolerance for consistent engagement and reliable performance. Manufacturing strictly adheres to ASME B18.6.3 specifications for dimensional accuracy and mechanical properties. Environmental compliance is verified through RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) certifications, ensuring restricted substance compliance for global distribution. The complete threading along the 1 1/4" length maintains uniform strength characteristics throughout the fastener body.