S-91500A338 1/4"-20 x 7/8" ASME B18.6.3 Stainless Steel Phillips Flat Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance in harsh environments thanks to 316 stainless steel construction and passivated finish
• Exceptional mechanical strength with a 70,000 psi tensile strength and Rockwell B80 hardness for reliable, long-term performance
• Optimized for flush mounting with a standard 82° countersink angle and flat head design for a clean, secure fit
• Reliable and efficient installation provided by the No. 3 Phillips drive and fully threaded UNC coarse thread design
• Precision thread fit with Class 2A tolerance ensuring consistent engagement and vibration resistance
• Compliance with major industry standards including ASME B18.6.3 for dimensional accuracy and material quality
• Safe for regulated industries with full compliance to RoHS 3 and REACH environmental directives

Professional Applications & Engineering Value

This 316 Stainless Steel Flat Head Phillips Screw is engineered to solve critical challenges in demanding industrial settings. Its passivated finish and marine-grade 316 stainless steel material provide outstanding resistance to chemicals, saltwater, and other corrosive agents, making it ideal for marine, chemical processing, and food industry applications. The fully threaded UNC coarse thread and Class 2A thread fit ensure quick assembly and secure fastening in materials where vibration loosening is a concern. The flat head with an 82° countersink allows for a flush surface finish, essential for applications in machinery, enclosures, and structural assemblies where protrusions are not permissible. This combination of high tensile strength and corrosion resistance delivers long-term reliability, reducing maintenance frequency and downtime in critical operations.

Specification Summary & Compliance

This screw features a 1/4"-20 UNC coarse thread with a Class 2A thread fit for precise dimensional accuracy. It is manufactured in compliance with the ASME B18.6.3 standard, ensuring consistent quality and performance. The product is fully RoHS 3 (2015/863/EU) Compliant and REACH (EC 1907/2006) Compliant, meeting stringent environmental and safety regulations for use in various global markets.