S-91253A810 5/8"-11 x 4" ASTM F835 Alloy Steel Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Exceptional corrosion resistance with black-oxide coating, ideal for harsh industrial environments
• Superior tensile strength of 130,000 psi ensures reliable performance under heavy loads
• Precise Class 3A thread fit provides secure fastening with minimal risk of cross-threading
• Partially threaded design allows for controlled clamping force in critical assembly applications
• Heavy-duty 3/8" hex drive enables high-torque installation without stripping
• 82° countersink angle ensures flush mounting for clean, professional finishes
• Full regulatory compliance with ASTM F835, RoHS 3, and REACH standards for global acceptance

Professional Applications & Engineering Value

Engineered for demanding industrial applications, these black-oxide alloy steel flat head screws deliver exceptional performance where corrosion resistance and structural integrity are paramount. The 5/8"-11 UNC coarse thread spacing provides superior holding power in soft materials and rapid installation in production environments. With Rockwell C37 hardness and 130,000 psi tensile strength, these partially threaded screws maintain clamping force in vibration-prone assemblies while the 82° countersink angle creates seamless surface finishes. Ideal for heavy machinery, structural steel connections, and outdoor equipment where corrosion resistant fasteners must withstand environmental challenges without compromising mechanical properties.

Specification Summary & Compliance

Manufactured to precise Class 3A thread fit tolerances with UNC thread form and coarse thread spacing for optimal engagement. These 4" length flat head screws feature partial threading with minimum 1 3/4" thread length and comply with ASTM F835 specifications for mechanical properties. Full compliance with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations ensures environmental responsibility and global market acceptance.