S-90471A449 5/16"-18 x 1" ASME B18.6.3 Steel Phillips Flat Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with zinc-plated steel construction for extended service life in demanding environments
• Exceptional holding power with 60,000 psi tensile strength and Rockwell B70 hardness for reliable fastening performance
• Quick installation and removal with No. 4 Phillips drive that prevents cam-out and reduces tool slippage
• Optimal material engagement through fully threaded 5/16"-18 UNC coarse threads for maximum grip strength
• Flush mounting capability with standard 100° countersink angle that sits perfectly flush with surfaces
• Precision thread fit with Class 2A thread tolerance ensuring smooth assembly and consistent performance
• Regulatory compliance assurance meeting ASME B18.6.3 standards and RoHS/REACH environmental regulations

Professional Applications & Engineering Value

These zinc-plated steel flat head screws deliver critical engineering solutions where flush surface mounting and corrosion resistance are paramount. The combination of 5/16"-18 UNC coarse threads and fully threaded design provides maximum thread engagement in various materials, preventing loosening under vibration while the Phillips No. 4 drive ensures efficient installation without specialized tools. Ideal for industrial equipment, machinery assembly, and metal fabrication applications, these flat head fasteners address common challenges of surface protrusion and environmental exposure. The 1" length offers versatile application across multiple material thicknesses, making them essential components in manufacturing, maintenance, and repair operations where reliability cannot be compromised.

Specification Summary & Compliance

Manufactured to exacting standards with Class 2A thread fit tolerance for consistent assembly performance. These inch system screws comply with ASME B18.6.3 specifications for dimensional accuracy and mechanical properties. The product meets RoHS 3 (2015/863/EU) compliance for hazardous substance restrictions and REACH (EC 1907/2006) regulations for chemical safety. Right-hand threaded with standard UNC coarse thread profile and 100° countersink angle per industrial standards.