S-90275A604 5/16"-18 x 5" ASME B18.6.3 Steel Slotted Flat Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with zinc-plated steel construction for extended service life in demanding environments
• High tensile strength of 60,000 psi ensures reliable fastening under heavy loads and vibration
• Rockwell B70 hardness provides excellent durability and resistance to wear and deformation
• Class 2A thread fit offers optimal assembly clearance for efficient installation while maintaining secure connections
• 82° countersink angle enables flush mounting for clean, professional finishes in various applications
• Fully threaded design allows for maximum grip length and adjustable positioning along the entire shank
• Coarse UNC threading provides quick installation and superior resistance to loosening in wood and soft materials

Professional Applications & Engineering Value

This 5/16"-18 UNC flat head slotted screw delivers exceptional engineering value for industrial assembly applications where flush mounting and high-strength fastening are critical. The zinc-plated steel construction provides reliable corrosion protection in manufacturing environments, while the 60,000 psi tensile strength ensures joint integrity under dynamic loads. The fully threaded coarse UNC pattern enables rapid installation in wood, plastic, and soft metals, reducing assembly time. The 82° countersink angle and flat head design create seamless surfaces ideal for machinery, furniture, and equipment where protruding fasteners are unacceptable. These industrial screws solve common challenges of vibration resistance, corrosion protection, and aesthetic requirements in professional applications.

Specification Summary & Compliance

This fastener features Class 2A thread fit per UNC standards, ensuring proper assembly clearance and interchangeability. Manufactured to ASME B18.6.3 specifications for dimensional accuracy and performance reliability. Compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, making them suitable for global industrial applications. The right-hand thread direction and coarse thread spacing provide optimal engagement in various materials while maintaining the specified 0.313" thread diameter and 5" length for consistent performance.