S-91858A544 1/4"-20 x 1 1/4" ASME B18.6.3 Stainless Steel Slotted Flat Head Screws

Key Features & Benefits at a Glance

• Exceptional corrosion resistance with 316 stainless steel construction and passivated finish, ideal for harsh marine and chemical environments
• Reliable fastening performance with 70,000 psi tensile strength and Rockwell B80 hardness for demanding industrial applications
• Precise thread engagement through Class 2A UNC coarse threading ensuring secure connections in various materials
• Full-length threading provides maximum grip and load distribution across the entire fastener length
• Standard flat head design with 82° countersink angle allows for flush mounting in assembled components
• Comprehensive compliance with ASME B18.6.3 manufacturing standards and environmental regulations including RoHS 3 and REACH
• Slotted drive compatibility for easy installation with standard screwdrivers in maintenance and assembly operations

Professional Applications & Engineering Value

Engineered for demanding industrial environments, this 316 stainless steel flat head screw delivers superior performance where corrosion resistance is critical. The combination of passivated finish and marine-grade 316 stainless steel provides exceptional protection against saltwater, chemicals, and extreme weather conditions, making it ideal for marine equipment, chemical processing facilities, and offshore installations. The UNC coarse threading with Class 2A fit ensures reliable engagement in both metal and composite materials, while the fully threaded design maximizes clamping force distribution. The flat head configuration with standard 82° countersink enables seamless flush mounting, preventing protrusion issues in precision assemblies and reducing snag hazards in moving machinery applications.

Specification Summary & Compliance

This 1/4"-20 x 1-1/4" flat head screw features precision UNC coarse threading with Class 2A thread fit tolerance for consistent performance. Manufactured in compliance with ASME B18.6.3 specifications for dimensional accuracy and mechanical properties. The product meets RoHS 3 (2015/863/EU) compliance for hazardous substance restrictions and REACH (EC 1907/2006) compliance for chemical safety regulations. The 316 stainless steel material with passivated surface treatment ensures long-term durability in corrosive environments while maintaining the specified mechanical properties of 70,000 psi tensile strength and Rockwell B80 hardness.