S-91263A715 1/4"-28 x 3/8" ASTM F835 Alloy Steel Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Exceptional corrosion resistance with zinc-plated alloy steel construction, extending service life in harsh industrial environments
• Superior thread engagement and vibration resistance achieved through Class 3A fine UNF threads, ensuring reliable long-term fastening
• High-strength performance with 130,000 psi tensile strength and Rockwell C39 hardness for demanding mechanical applications
• Efficient installation and flush mounting with 5/32" hex drive and 82° countersink angle for seamless surface finishing
• Full-threaded design providing maximum grip length and uniform stress distribution across the entire fastener
• Regulatory compliance assurance meeting ASTM F835 specifications while being RoHS 3 and REACH compliant for global supply chain integration
• Precision-engineered dimensions with standardized UNF thread form ensuring perfect compatibility with existing industrial equipment

Professional Applications & Engineering Value

Engineered for high-performance industrial fastening, these 1/4"-28 UNF Class 3A flat head screws deliver critical advantages in precision assembly applications. The zinc-plated alloy steel construction provides essential corrosion protection for machinery, automotive components, and electrical enclosures exposed to demanding environments. The fine UNF thread profile combined with Class 3A thread fit ensures superior vibration resistance in dynamic systems, while the 82° countersink angle enables flush mounting in precision-machined surfaces. With 130,000 psi tensile strength, these fully threaded screws maintain structural integrity under extreme mechanical stress, making them ideal for critical joints in manufacturing equipment, aerospace assemblies, and heavy-duty industrial machinery where failure is not an option.

Specification Summary & Compliance

This flat head screw features precision 1/4"-28 UNF Class 3A threads with fine thread spacing and right-hand thread direction. Manufactured to ASTM F835 specifications with dimensional accuracy including 0.531" head diameter, 0.161" head height, and 3/8" length. The fastener is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring environmental responsibility and global market acceptance for industrial procurement.