S-91771A849 4-40 x 7/32" ASME B18.6.3 Stainless Steel Phillips Flat Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with passivated 18-8 stainless steel construction, ideal for harsh industrial environments
• Exceptional mechanical strength with 70,000 psi tensile strength and Rockwell B80 hardness for reliable load-bearing performance
• Precise thread engagement through Class 2A thread fit and UNC coarse threading, ensuring secure fastening in various materials
• Streamlined installation with Phillips No. 1 drive and 82° countersink angle for flush mounting and reduced assembly time
• Full-threaded design provides maximum grip along the entire 7/32" length for enhanced holding power
• Regulatory compliance with ASME B18.6.3, RoHS 3, and REACH standards, guaranteeing safety and environmental responsibility
• Versatile flat head profile enables seamless surface integration in machinery, electronics, and precision equipment

Professional Applications & Engineering Value

These 4-40 UNC flat head screws deliver critical engineering advantages in demanding applications. The passivated 18-8 stainless steel material combats corrosion in humid or chemical-exposed settings, extending service life in industrial equipment, electronic enclosures, and automotive assemblies. The fully threaded coarse UNC design ensures rapid installation and superior pull-out resistance in metals and plastics, while the 82° countersink angle and Phillips No. 1 drive facilitate precise, flush mounting without protrusions. These flat head machine screws solve common issues like vibration loosening and material degradation, providing a reliable, standards-compliant fastening solution for OEM and MRO requirements.

Specification Summary & Compliance

This screw maintains Class 2A thread fit per UNC standards, ensuring dimensional accuracy and interchangeability. Manufacturing adheres to ASME B18.6.3 specifications for consistent quality. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming the absence of restricted hazardous substances. Additional specifications include a standard flat head profile, right-hand thread direction, and coarse thread spacing, all engineered to meet industrial fastening demands.