S-90273A542 1/4"-20 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 industrial environments
• High tensile strength of 60,000 psi ensures reliable fastening performance under substantial mechanical loads
• Class 2A thread fit provides optimal assembly efficiency while maintaining secure connections
• 82° countersink angle enables flush mounting for clean, professional finishes in various applications
• Rockwell B70 hardness rating delivers excellent durability and resistance to wear during installation and use
• Full threading design maximizes grip strength and distributes load evenly across the entire fastener length
• Phillips No. 3 drive offers secure tool engagement and efficient installation with standard driving tools

Professional Applications & Engineering Value

These 1/4"-20 UNC flat head screws provide exceptional engineering value for industrial assembly applications where flush mounting and high-strength fastening are critical. The zinc-plated steel construction offers reliable corrosion protection, making them ideal for machinery, equipment manufacturing, and structural applications exposed to environmental elements. The coarse thread spacing ensures quick installation and superior holding power in various materials, while the standard 82° countersink angle creates seamless surface finishes. These fully threaded fasteners distribute stress evenly, preventing localized failure points and ensuring long-term joint integrity in demanding industrial settings.

Specification Summary & Compliance

Manufactured to exacting ASME B18.6.3 standards with Class 2A thread fit tolerances for precision assembly. These UNC coarse thread screws feature 1/4"-20 threading with right-hand direction and are fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations. The flat head profile maintains standard dimensions with 0.477" head diameter and 1" length, ensuring compatibility with standard counterbore preparations across industrial applications.