S-91253A873 5/8"-18 x 2" ASTM F835 Alloy Steel Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Exceptional corrosion resistance with black-oxide coating protecting alloy steel in demanding industrial environments
• Superior load-bearing capacity with 130,000 psi tensile strength for heavy-duty applications
• Precise thread engagement through Class 3A fit and UNF fine threads ensuring vibration-resistant connections
• Optimized drive efficiency with 3/8" hex drive preventing cam-out during high-torque installation
• Flush mounting capability with 82° countersink angle for seamless surface integration
• Full-thread design providing maximum grip length and uniform stress distribution
• Regulatory compliance meeting ASTM F835, RoHS 3, and REACH standards for global industrial use

Professional Applications & Engineering Value

These black-oxide alloy steel flat head screws deliver critical performance advantages in industrial assembly where corrosion resistance and high clamp force are paramount. The UNF fine thread configuration maintains joint integrity under vibration, while the Rockwell C37 hardness ensures durability against wear. The hex drive system enables efficient installation in confined spaces, and the 82° countersink creates flush surfaces for aerodynamic or safety-critical applications. Engineered to prevent galvanic corrosion and withstand extreme mechanical stress, these fully threaded fasteners provide reliable, long-term performance in machinery, structural frameworks, and heavy equipment assemblies.

Specification Summary & Compliance

Manufactured to inch system specifications with Class 3A thread fit precision and UNF fine threading (5/8"-18). Complies with ASTM F835 manufacturing standards and maintains RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental compliance. Features 82° countersink angle and fully threaded design with verified 130,000 psi tensile strength and Rockwell C37 hardness ratings.