S-90275A599 5/16"-18 x 4" 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 fastening under substantial mechanical loads
• Rockwell B70 hardness provides excellent durability and resistance to wear during installation and use
• Class 2A thread fit offers optimal assembly clearance while maintaining secure connections
• 82° countersink angle enables flush mounting for clean, professional finishes in various applications
• UNC coarse threading facilitates quicker installation and reduced cross-threading risks
• Full threading along the 4" length allows for maximum adjustability and grip depth in assembled components

Professional Applications & Engineering Value

These zinc-plated steel flat head screws deliver exceptional engineering value through their robust material composition and precision UNC coarse threading. The combination of 60,000 psi tensile strength and Rockwell B70 hardness addresses critical industrial challenges including vibration-induced loosening and material fatigue. The standard 82° countersink angle ensures seamless integration in machinery, automotive assemblies, and structural frameworks where flush surface requirements are paramount. The zinc plating provides essential corrosion protection for applications exposed to environmental elements, while the slotted drive design offers compatibility with standard installation tools. These fully threaded 4" fasteners are engineered to maintain integrity in high-stress applications across manufacturing, construction, and heavy equipment sectors.

Specification Summary & Compliance

Manufactured to exacting inch system specifications with Class 2A thread fit tolerance ensuring precision assembly. These 5/16"-18 UNC coarse thread screws comply with ASME B18.6.3 manufacturing standards for dimensional accuracy and performance. The products are fully compliant with RoHS 3 (2015/863/EU) environmental directives and REACH (EC 1907/2006) regulations regarding substance restrictions, making them suitable for global industrial applications with strict regulatory requirements.