S-92949A857 5/16"-18 x 2 3/4" ASME B18.3, ASTM F879 Stainless Steel Button Head Hex-Drive Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 18-8 stainless steel construction and passivated finish, ideal for harsh industrial environments
• Exceptional thread reliability through Class 3A thread fit and UNC coarse threading, ensuring secure fastening in high-vibration applications
• High-torque installation capability with hex drive design and 3/16" drive size, enabling efficient assembly with standard tools
• Optimized load distribution from the rounded button head profile, reducing surface damage while maintaining strong clamping force
• Consistent mechanical performance with 70,000 psi tensile strength and Rockwell B55 hardness, providing reliable long-term service
• Full-thread engagement across the 2 3/4" length, maximizing pull-out resistance in demanding applications
• Regulatory compliance assurance meeting ASME B18.3, ASTM F879, RoHS 3, and REACH standards for global industrial use

Professional Applications & Engineering Value

This 18-8 stainless steel rounded head screw delivers critical performance advantages for industrial assembly challenges. The combination of Class 3A UNC coarse threading and fully threaded design provides superior resistance to vibration loosening in machinery, equipment manufacturing, and structural applications. The passivated finish enhances corrosion protection in environments exposed to moisture, chemicals, or outdoor conditions, while the hex drive configuration ensures high-torque installation without cam-out issues. With 70,000 psi tensile strength, this fastener maintains joint integrity under heavy loads, making it ideal for critical connections in construction, transportation, and industrial machinery where reliability is paramount.

Specification Summary & Compliance

Manufactured to precise dimensional standards with Class 3A thread fit and UNC coarse thread spacing (5/16"-18), this fastener ensures consistent performance across industrial applications. The screw conforms to ASME B18.3 specifications and ASTM F879 manufacturing standards, with full compliance to RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations. The Rockwell B55 hardness and dimensional accuracy guarantee reliable performance in demanding mechanical assemblies.