S-91253A088 2-64 x 1/4" ASTM F835 Alloy Steel Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with black-oxide coating, extending service life in demanding industrial environments.
• Exceptional tensile strength of 130,000 psi ensures reliable performance under high-stress conditions.
• Precision Class 3A thread fit guarantees secure, vibration-resistant fastening with minimal play.
• Fully threaded 2-64 UNF fine thread design provides maximum grip and load distribution in thin materials.
• 82° countersink angle and flat head profile enable flush mounting for a smooth, professional finish.
• Hex drive (0.050") compatibility allows for easy installation with standard tools, reducing assembly time.
• Rockwell C39 hardness offers excellent wear resistance and durability for long-term use.

Professional Applications & Engineering Value

This black-oxide alloy steel flat head screw is engineered to address critical challenges in precision assembly and high-vibration environments. The 2-64 UNF fine thread and Class 3A fit ensure tight tolerances, preventing loosening in applications like electronics, aerospace components, and machinery where reliability is paramount. The fully threaded design maximizes engagement in thin sheets or pre-tapped holes, distributing stress evenly to reduce the risk of stripping. Combined with the 82° countersink, it provides a seamless finish that meets aesthetic and functional requirements in automotive, industrial equipment, and OEM manufacturing. The black-oxide surface treatment adds a layer of corrosion protection, making it ideal for moderate environmental exposure without compromising on 130,000 psi tensile strength.

Specification Summary & Compliance

This screw adheres to ASTM F835 specifications for mechanical properties and dimensional accuracy, with a Class 3A thread fit per UNF standards ensuring precise engagement. It is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming the absence of restricted hazardous substances. The right-hand thread and fine thread spacing are manufactured to consistent tolerances, supporting reliable performance in regulated industrial applications.