S-91500A311 5-40 x 3/8" ASME B18.6.3 Stainless Steel Phillips Flat Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 316 stainless steel construction and passivated finish, ideal for harsh environments and extended service life
• Exceptional mechanical strength with 70,000 psi tensile strength and Rockwell B80 hardness for reliable performance under high stress
• Precision thread engagement with Class 2A UNC coarse threads ensuring secure fastening and easy installation
• Flush mounting capability featuring a standard 82° countersink angle flat head for a smooth, professional finish
• Efficient drive system with No. 2 Phillips drive providing positive torque transfer and reduced cam-out risk
• Full thread coverage along the 3/8" length for maximum grip and holding power in various material thicknesses
• Regulatory compliance assurance meeting ASME B18.6.3 specifications and environmental standards (RoHS 3, REACH)

Professional Applications & Engineering Value

These 5-40 UNC flat head screws are engineered to address critical challenges in industrial assembly where corrosion resistance and mechanical reliability are paramount. The 316 stainless steel material, enhanced by a passivated finish, provides exceptional protection against chemical exposure and atmospheric corrosion, making these Phillips drive screws ideal for marine, chemical processing, and food equipment applications. The fully threaded coarse UNC thread design ensures rapid installation and superior pull-out resistance in softer materials, while the 82° countersink angle allows for seamless flush mounting in precision machinery and structural components. With consistent performance across temperature variations and demanding operational cycles, these screws deliver long-term fastening integrity while reducing maintenance frequency and replacement costs.

Specification Summary & Compliance

This flat head screw features precise Class 2A thread fit with 5-40 UNC coarse threads and right-hand threading. Manufacturing conforms to ASME B18.6.3 standards, ensuring dimensional accuracy and interchangeability. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming the absence of restricted hazardous substances.