S-91500A339 1/4"-20 x 1 1/8" ASME B18.6.3 Stainless Steel Phillips Flat Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 316 stainless steel construction, ideal for harsh environments and chemical exposure
• Exceptional mechanical strength with 70,000 psi tensile strength and Rockwell B80 hardness for reliable load-bearing performance
• Secure and flush installation thanks to the standard 82° countersink angle and flat head design
• Efficient driving and reduced cam-out with Phillips No. 3 drive for consistent torque application
• Versatile coarse threading (UNC) ensuring quick assembly and strong holding power in various materials
• Full 1-1/8" threading provides maximum grip length and uniform stress distribution
• Precision manufacturing with Class 2A thread fit for consistent, reliable fastening

Professional Applications & Engineering Value

This 1/4"-20 UNC flat head screw in 316 stainless steel with a passivated finish is engineered to address critical industrial challenges, including corrosion in marine, chemical processing, and outdoor applications. The fully threaded coarse UNC design ensures rapid installation and robust clamping force, while the flat head with 82° countersink allows for seamless, flush mounting in machinery, panels, and structural components. Its 70,000 psi tensile strength and consistent Class 2A thread fit minimize failure risks, making it a dependable choice for high-stress environments where durability and compliance are paramount.

Specification Summary & Compliance

This screw meets ASME B18.6.3 specifications, ensuring dimensional accuracy and performance reliability. It features a Class 2A thread fit for consistent engagement and is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming its suitability for global industrial use without hazardous substances.