S-91770A095 4-40 x 5/16" ASME B18.6.3 Stainless Steel Truss Head Phillips Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance from passivated 18-8 stainless steel construction, ideal for harsh industrial environments
• Exceptional tensile strength rated at 70,000 psi ensures reliable performance under heavy loads
• Optimized thread engagement with Class 2A UNC coarse threads provides secure fastening and vibration resistance
• Enhanced drive stability with No. 1 Phillips drive and wide truss head design for improved torque transmission
• Full threading capability allows maximum grip length and consistent clamping force across applications
• Industry compliance assurance meeting ASME B18.6.3 specifications for dimensional accuracy and performance
• Environmental regulation compliance with RoHS 3 and REACH standards for safe, sustainable manufacturing

Professional Applications & Engineering Value

These 4-40 UNC rounded truss head screws deliver critical engineering advantages in demanding applications where corrosion resistance and mechanical reliability are paramount. The passivated 18-8 stainless steel construction provides exceptional protection against oxidation and chemical degradation, making them ideal for marine, food processing, and outdoor equipment applications. The combination of coarse UNC threads with Class 2A fit ensures rapid installation and secure fastening in various materials, while the wide truss head design distributes clamping force effectively, preventing surface damage and maintaining joint integrity. The fully threaded right-hand configuration offers maximum adjustability and holding power, solving common challenges of loosening under vibration and dynamic loads in industrial machinery and electronic enclosures.

Specification Summary & Compliance

Manufactured to precise dimensional standards with Class 2A thread fit and UNC coarse threading (4-40 size) ensuring consistent performance across applications. These screws conform to ASME B18.6.3 mechanical and dimensional specifications, guaranteeing interchangeability and reliability. Compliance with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations confirms environmental safety and restricted substance adherence. The combination of 70,000 psi tensile strength and Rockwell B70 hardness provides documented mechanical performance for engineering calculations and safety factors.