S-91253A746 1/2"-13 x 6 1/2" ASTM F835 Alloy Steel Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Exceptional tensile strength of 130,000 PSI provides reliable holding power in demanding structural and heavy machinery applications.
• Superior corrosion resistance from the black-oxide finish on alloy steel, extending service life in harsh industrial environments.
• Precise Class 3A thread fit ensures easy assembly and a secure, vibration-resistant connection, minimizing the risk of loosening.
• High Rockwell C39 hardness offers excellent wear resistance and durability, reducing the need for frequent replacements.
• 82° countersink angle and flat head design allows for a flush, clean finish, ideal for applications where protruding fasteners are not acceptable.
• Hex drive (5/16") enables high-torque installation with common tools, speeding up assembly and maintenance processes.
• Partially threaded shank provides enhanced clamping force on the materials being joined, improving joint integrity.

Professional Applications & Engineering Value

This 1/2"-13 UNC flat head screw is engineered to solve critical challenges in industrial assembly. The black-oxide alloy steel construction combats rust and corrosion, making it ideal for outdoor equipment, automotive frames, and machinery exposed to moisture. The coarse UNC thread and Class 3A fit facilitate quick, reliable fastening in materials like steel and cast iron, resisting vibration-induced failure. The partially threaded design concentrates clamping force precisely where needed, preventing material distortion. Its high tensile strength and hardness ensure it can withstand extreme loads and stresses in heavy-duty fastening applications, from construction to manufacturing, delivering long-term reliability and reducing maintenance downtime.

Specification Summary & Compliance

This screw adheres to precise dimensional standards, including a Class 3A thread fit for superior accuracy and a 1/2"-13 UNC coarse thread. It is manufactured in compliance with ASTM F835 specifications, ensuring consistent quality and performance. The product is also certified as RoHS 3 (2015/863/EU) Compliant and REACH (EC 1907/2006) Compliant, confirming it meets stringent environmental and safety regulations for use in various global markets.