S-90585A054 5/16"-18 x 7/8" ASME B18.3 Stainless Steel Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 316 stainless steel construction and passivated finish, ideal for harsh chemical and marine environments
• Exceptional mechanical strength with 70,000 psi tensile strength and Rockwell B55 hardness for reliable performance under heavy loads
• Precise thread engagement through Class 3A thread fit and UNC coarse threading, ensuring secure fastening and vibration resistance
• Optimized flush mounting with standard 82° countersink angle and flat head design for seamless surface integration
• Efficient installation using hex drive (3/16") for high torque application without cam-out risks
• Full-length threading providing maximum grip and load distribution across the entire 7/8" length
• Regulatory compliance meeting ASME B18.3 specifications and environmental standards (RoHS 3, REACH) for industrial applications

Professional Applications & Engineering Value

Engineered for demanding industrial environments, these 316 stainless steel flat head screws deliver exceptional performance where corrosion resistance and structural integrity are paramount. The combination of UNC coarse threading and Class 3A thread fit ensures reliable fastening in vibration-prone applications while maintaining precise dimensional accuracy. The passivated finish provides an additional protective layer against chemical exposure and atmospheric corrosion, making these fully threaded screws ideal for marine equipment, chemical processing plants, and food processing machinery. The 82° countersink angle and flat head profile allow for flush mounting in precision assemblies, while the hex drive design enables high-torque installation without stripping. These features collectively address common industrial challenges including material degradation, joint failure, and maintenance accessibility in critical applications.

Specification Summary & Compliance

Manufactured to exacting standards with Class 3A thread fit per UNC specifications and dimensional compliance with ASME B18.3. The screws feature precise head diameter tolerance (-0.056" to 0") and maintain full compliance with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations. Thread specifications include 5/16"-18 UNC coarse spacing with right-hand orientation, supported by 70,000 psi tensile strength verification and Rockwell B55 hardness rating for consistent performance across industrial applications.