S-91771A078 2-56 x 5/16" 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 80,000 psi tensile strength and Rockwell B80 hardness for reliable performance under stress
• Precise flush mounting enabled by standard flat head profile with 82° countersink angle for seamless surface integration
• Optimized drive engagement through Phillips No. 1 drive design, reducing cam-out risks during installation
• Reliable thread performance with UNC coarse threading and Class 2A fit, ensuring consistent fastening in various materials
• Full-threaded design providing maximum grip length and superior holding power across the entire shank
• Regulatory compliance assurance meeting ASME B18.6.3 standards and environmental regulations for global industrial use

Professional Applications & Engineering Value

Engineered for demanding industrial applications, these 2-56 UNC flat head Phillips machine screws deliver critical performance advantages in machinery assembly, electronic enclosures, and precision equipment. The passivated 18-8 stainless steel construction provides exceptional corrosion resistance, making them ideal for environments exposed to moisture, chemicals, or temperature variations. The combination of 80,000 psi tensile strength and Rockwell B80 hardness ensures reliable performance in high-vibration applications while maintaining structural integrity. The fully threaded design with UNC coarse threads offers superior pull-out resistance in various substrate materials, while the standard 82° countersink angle enables perfect flush mounting for safety and aesthetic requirements in finished products.

Specification Summary & Compliance

This flat head screw features precise Class 2A thread fit tolerances with UNC coarse threading (2-56 size) and right-hand thread direction. Manufacturing complies with ASME B18.6.3 specifications for dimensional accuracy and performance standards. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, ensuring safe use across global industrial markets. The 5/16" length and fully threaded configuration provide consistent fastening performance in accordance with established industrial standards.