S-91771A564 1/4"-28 x 1 1/2" 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 tensile strength of 80,000 psi ensures reliable performance under high-stress applications.
• Precise Class 2A thread fit guarantees smooth assembly and secure fastening with consistent engagement.
• Fully threaded design provides maximum grip and load distribution along the entire 1-1/2" length.
• Standard 82° countersink angle allows for a flush, professional finish in countersunk holes.
• No. 3 Phillips drive offers efficient installation with common tools, reducing assembly time.
• Compliance with major regulations including RoHS 3 and REACH ensures environmental and safety standards are met.

Professional Applications & Engineering Value

This 1/4"-28 UNF flat head screw is engineered to address critical challenges in industrial assembly, such as vibration resistance and material degradation. The passivated 18-8 stainless steel provides excellent protection against corrosion, extending service life in demanding settings like machinery, automotive, and outdoor equipment. Its fine thread spacing and Class 2A thread fit ensure tight, reliable connections that minimize loosening under dynamic loads. The fully threaded design enhances holding power, making it suitable for applications where shear and tensile strength are paramount. With an 82° countersink angle and Phillips drive, it facilitates quick, flush installations, reducing labor costs and improving overall assembly efficiency in industrial screws applications.

Specification Summary & Compliance

This screw adheres to ASME B18.6.3 specifications, with precise Class 2A thread fit and UNF fine threads for consistent performance. It meets RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) compliance, ensuring it is free from hazardous substances and suitable for global industrial use.