S-91773A113 4-40 x 3/4" ASME B18.6.3 Stainless Steel Round Head Phillips Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 18-8 stainless steel construction and passivated finish, ideal for harsh industrial environments
• Exceptional mechanical strength with 100,000 psi tensile strength and Rockwell B100 hardness for reliable load-bearing performance
• Optimized thread engagement through Class 2A thread fit and fully threaded design, ensuring maximum holding power and vibration resistance
• Streamlined installation with Phillips No. 1 drive and rounded head profile, providing secure tool engagement and reduced installation time
• Industry-standard compatibility with 4-40 UNC coarse threading, making them interchangeable with existing industrial equipment
• Regulatory compliance assurance meeting ASME B18.6.3 specifications and environmental standards including RoHS 3 and REACH
• Enhanced durability through precise manufacturing standards, delivering long-term performance in demanding applications

Professional Applications & Engineering Value

These 4-40 UNC rounded head Phillips screws deliver critical engineering value in industrial fastening applications where corrosion resistance and mechanical reliability are paramount. The 18-8 stainless steel composition, enhanced by passivated finish, provides exceptional protection against chemical exposure and environmental degradation in manufacturing, electronics assembly, and outdoor equipment. The coarse thread design ensures rapid installation and superior grip in various materials, while the fully threaded configuration maximizes surface contact for enhanced load distribution. The Phillips No. 1 drive system offers reliable torque transmission, reducing cam-out incidents during high-volume assembly operations. These screws effectively address common industrial challenges including vibration loosening, material compatibility issues, and regulatory compliance requirements.

Specification Summary & Compliance

Manufactured to precise dimensional standards with Class 2A thread fit tolerance and UNC coarse threading (4-40 size). The screws feature a 3/4" length with 0.211" head diameter and comply with ASME B18.6.3 mechanical standards. Environmental compliance includes RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring safe use in regulated industries. The manufacturing process maintains consistent thread spacing and right-hand thread direction for uniform performance across production batches.