S-91500A345 1/4"-28 x 1" ASME B18.6.3 Stainless Steel Phillips Flat Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance from 316 Stainless Steel and passivated finish, ideal for harsh environments and extended service life
• High-strength performance with 70,000 psi tensile strength and Rockwell B80 hardness for reliable load-bearing in demanding applications
• Precise fine thread engagement with 1/4"-28 UNF and Class 2A fit, ensuring secure fastening and vibration resistance
• Optimal flush mounting with a standard 82° countersink angle and flat head design for a smooth, professional finish
• Efficient installation using a No. 3 Phillips drive, reducing slippage and tool wear during assembly
• Full threading along the 1" length provides maximum grip and adjustment flexibility in various material thicknesses
• Regulatory compliance and quality assurance meeting ASME B18.6.3, RoHS 3, and REACH standards for safe, reliable use

Professional Applications & Engineering Value

This 1/4"-28 UNF flat head screw is engineered to address critical challenges in industrial and marine settings where corrosion resistance and mechanical strength are paramount. Constructed from 316 Stainless Steel with a passivated finish, it effectively resists pitting and chemical degradation, making it suitable for offshore equipment, chemical processing plants, and food-grade machinery. The fine UNF thread and Class 2A fit ensure tight, secure connections that minimize loosening under dynamic loads, while the 82° countersink angle allows for seamless integration into precision-machined components. Its fully threaded design and Phillips drive facilitate quick, reliable installation in assemblies requiring flush surfaces and consistent clamping force, reducing maintenance needs and enhancing operational longevity.

Specification Summary & Compliance

This screw adheres to ASME B18.6.3 specifications, ensuring dimensional accuracy and performance reliability. Threading conforms to UNF fine thread standards with a Class 2A fit for consistent engagement. It is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, guaranteeing environmental safety and material integrity. Key attributes include a 1" length, right-hand thread direction, and manufacturing that meets defined hardness and tensile strength criteria for industrial use.