S-90275A582 5/16"-18 x 7/8" ASME B18.6.3 Steel Slotted Flat Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with zinc plating for extended service life in demanding industrial environments.
• High tensile strength of 60,000 psi ensures reliable performance under heavy loads and vibration.
• Class 2A thread fit provides smooth assembly and consistent engagement for efficient installation.
• 82° countersink angle allows for a flush, low-profile finish in countersunk applications.
• Fully threaded design offers maximum grip and holding power along the entire screw length.
• Rockwell B70 hardness provides excellent durability and resistance to wear and deformation.
• Compliance with ASME B18.6.3, RoHS 3, and REACH guarantees quality, safety, and environmental standards are met.

Professional Applications & Engineering Value

This 5/16"-18 UNC flat head screw is engineered to solve critical fastening challenges in industrial assembly. The zinc-plated steel construction offers robust protection against rust and corrosion, making it ideal for machinery, automotive, and outdoor equipment where exposure to harsh conditions is common. The coarse UNC thread and Class 2A thread fit ensure quick, secure installation with reduced risk of cross-threading, while the slotted drive provides compatibility with standard tools. The 82° countersink angle and flat head design allow for a seamless, flush mount, preventing snagging and improving aesthetic integration in metal, wood, and composite materials. These features collectively enhance assembly speed, reduce maintenance needs, and provide long-term reliability in high-stress applications.

Specification Summary & Compliance

This screw features a 5/16"-18 UNC thread with Class 2A dimensional accuracy for consistent fit. It is manufactured in compliance with ASME B18.6.3 specifications and meets RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulatory requirements, ensuring it is free of hazardous substances and safe for various industrial uses.