S-91321A131 1/4"-20 x 1" MS35190-291, NASM35190 Steel Phillips Flat Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with cadmium plating that protects against harsh industrial environments
• Exceptional tensile strength rated at 60,000 psi for reliable performance in demanding applications
• Easy installation and removal with Phillips No. 3 drive that prevents cam-out and reduces tool wear
• Precise flush mounting thanks to the 82° countersink angle and standard flat head profile
• Consistent thread engagement with Class 2A fit UNC coarse threads ensuring secure fastening
• Maximum holding power through fully threaded design that distributes load evenly across the entire length
• Guaranteed quality assurance through compliance with MS35190-291/NASM35190 specifications

Professional Applications & Engineering Value

These 1/4"-20 UNC flat head screws deliver exceptional engineering value in industrial settings where vibration resistance and reliable fastening are critical. The cadmium-plated steel construction provides excellent corrosion protection for machinery, equipment assemblies, and structural components exposed to demanding conditions. The fully threaded right-hand design with coarse UNC threading ensures rapid installation and superior holding strength, while the 82° countersink angle creates a flush surface finish that eliminates protrusions in precision assemblies. The Phillips No. 3 drive offers efficient torque transmission without slippage, making these industrial screws ideal for production lines where speed and reliability are paramount. These heavy-duty fasteners solve common challenges of loosening under stress while maintaining consistent performance in automotive, manufacturing, and construction applications.

Specification Summary & Compliance

Manufactured to exacting inch measurement standards with precise Class 2A thread fit tolerance for consistent performance. The UNC coarse thread specification (1/4"-20) ensures optimal engagement in various materials. These steel flat head screws comply with MS35190-291/NASM35190 military specifications and meet industry standards for dimensional accuracy and mechanical properties. The product conforms to RoHS and REACH environmental regulations, providing assurance of material safety and compliance in global industrial markets.