S-90585A590 5/16"-18 x 2" ASME B18.3 Stainless Steel Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Maximum corrosion resistance with 316 stainless steel construction and passivated finish, ideal for harsh chemical and marine environments
• Superior mechanical strength delivering 70,000 psi tensile strength and Rockwell B55 hardness for heavy-duty load-bearing applications
• Precise Class 3A thread fit ensures secure, vibration-resistant fastening with minimal risk of loosening in critical assemblies
• Full threading and 82° countersink provides complete engagement and flush mounting for streamlined industrial designs
• 3/16" hex drive compatibility enables high-torque installation with standard tools, reducing assembly time and labor costs
• Compliance with ASME B18.3, RoHS 3, and REACH guarantees quality assurance and environmental safety for global supply chains
• Coarse UNC thread spacing facilitates quick installation and superior pull-out resistance in various base materials

Professional Applications & Engineering Value

Engineered for demanding industrial environments, these 316 stainless steel flat head screws solve critical challenges in chemical processing, marine equipment, and offshore installations where corrosion resistance is paramount. The passivated finish enhances surface durability against chlorides and acidic exposure, while the Class 3A thread fit maintains clamping force under vibration and thermal cycling. With full threading and 82° countersink, these UNC coarse thread fasteners ensure rapid assembly in structural frameworks, machinery guards, and piping systems—reducing maintenance downtime and lifecycle costs through superior material integrity and ASME B18.3 compliance.

Specification Summary & Compliance

This 5/16"-18 UNC flat head screw maintains precision Class 3A thread fit per ASME standards, with dimensional controls including head diameter (0.656"), length (2"), and 82° countersink angle. Manufacturing adheres to ASME B18.3 specifications, with full compliance to RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) for hazardous substance restrictions. The right-hand coarse threading and fully threaded design ensure consistent performance in high-stress applications.