S-98164A268 5/16"-18 x 1" ASME B18.3, ASTM F879 Stainless Steel Button Head Hex-Drive Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 316 stainless steel construction, ideal for harsh industrial environments and chemical exposure
• Exceptional mechanical strength with 70,000 psi tensile strength and Rockwell B55 hardness for reliable performance under high stress
• Precise thread engagement through Class 3A fit and UNC coarse spacing, ensuring secure fastening and vibration resistance
• Enhanced durability and surface protection with passivated finish, reducing wear and extending service life
• Efficient installation and removal with hex drive design, allowing for high torque application without slippage
• Full threading for maximum grip across the entire 1" length, providing uniform clamping force in various materials
• Compliance with major industry standards including ASME B18.3 and ASTM F879, guaranteeing quality and interoperability

Professional Applications & Engineering Value

These 316 stainless steel rounded head screws deliver critical performance in demanding applications where corrosion resistance and mechanical integrity are paramount. The passivated finish provides an additional protective layer against oxidation and chemical degradation, making them ideal for marine, chemical processing, and food industry equipment. With UNC coarse threads and Class 3A fit, they ensure rapid assembly and reliable thread engagement in soft metals or plastics, reducing the risk of cross-threading. The hex drive and rounded button head design facilitate easy access in confined spaces while maintaining a low-profile appearance. Engineered to withstand vibrational stresses and environmental exposure, these screws offer long-term reliability in structural assemblies, machinery, and outdoor installations, minimizing maintenance needs and downtime.

Specification Summary & Compliance

This screw features precise inch system measurements with a 5/16"-18 UNC thread size, coarse spacing, and Class 3A thread fit for high precision. Manufacturing adheres to ASME B18.3 and ASTM F879 specifications, ensuring dimensional accuracy and performance consistency. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming the absence of hazardous substances and supporting environmentally responsible procurement.