S-90729A412 1/4"-20 x 3/4" Stainless Steel Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 316 stainless steel construction and passivated finish, ideal for harsh chemical and marine environments
• Exceptional mechanical strength with 70,000 psi tensile strength and Rockwell B70 hardness for reliable performance under heavy loads
• Precision thread engagement with Class 3A UNC coarse threading ensuring secure fastening and vibration resistance
• Optimized flush mounting featuring undercut flat head design with 100° countersink angle for seamless surface installation
• Enhanced driving torque capability with 1/8" hex drive providing superior grip and reduced tool slippage
• Full thread coverage across the entire 3/4" length for maximum holding power in various material thicknesses
• Regulatory compliance assurance meeting RoHS 3 and REACH standards for environmentally responsible manufacturing

Professional Applications & Engineering Value

This 316 stainless steel flat head screw delivers exceptional value in demanding industrial applications where corrosion resistance and mechanical integrity are paramount. The combination of Class 3A UNC coarse threading provides superior engagement in soft materials and faster installation times, while the passivated finish significantly enhances pitting and crevice corrosion resistance in chemical processing, marine, and food industry applications. The undercut flat head profile with 100° countersink angle ensures flush mounting without protrusion, preventing snagging and maintaining clean aesthetic lines. Engineered with 70,000 psi tensile strength, this fully threaded hex drive screw maintains structural integrity in high-vibration environments, making it ideal for machinery assembly, structural frameworks, and equipment subjected to thermal cycling and harsh operating conditions.

Specification Summary & Compliance

This fastener features precision 1/4"-20 UNC coarse threading with Class 3A thread fit for tight tolerance applications, maintaining dimensional accuracy with head diameter tolerance of -0.01" to 0". Manufactured in compliance with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental standards, ensuring restricted substance compliance. The screw maintains consistent mechanical properties with Rockwell B70 hardness and is fully threaded along its 3/4" length for uniform load distribution across engaged materials.