S-91263A196 3/8"-16 x 4" ASME B18.3 Alloy Steel Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Exceptional tensile strength of 120,000 psi ensures reliable performance in demanding applications, reducing the risk of fastener failure.
• Superior corrosion resistance from zinc plating protects against rust and extends service life in harsh industrial environments.
• Precise Class 3A thread fit provides tighter tolerances for secure, vibration-resistant assemblies and improved load distribution.
• Partially threaded design allows for controlled clamping force and easier alignment in specific assembly scenarios.
• 82° countersink angle enables a flush, professional finish that minimizes protrusion and improves safety.
• Hex drive (7/32") offers high torque transmission and secure installation with standard tools, reducing slippage and damage.
• Compliance with ASME B18.3, RoHS 3, and REACH ensures adherence to industry standards and environmental regulations for global supply chain compatibility.

Professional Applications & Engineering Value

This 3/8"-16 UNC flat head screw is engineered to address critical challenges in industrial fastening, such as vibration loosening and material fatigue. Constructed from zinc-plated alloy steel, it combines high tensile strength with excellent corrosion resistance, making it ideal for heavy-duty machinery, structural frameworks, and outdoor equipment. The coarse UNC thread and Class 3A fit ensure rapid assembly and reliable holding power in metals and composites, while the partial threading and 82° countersink provide a secure, flush mount that reduces stress concentrations. These features make it a top choice for applications requiring durability, precision, and compliance with stringent standards like ASME B18.3.

Specification Summary & Compliance

This screw adheres to precise dimensional standards, including a Class 3A thread fit for superior accuracy and a UNC coarse thread (3/8"-16) with a minimum thread length of 1 1/4". It is manufactured in accordance with ASME B18.3 specifications and is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006), ensuring environmental safety and regulatory acceptance in industrial markets.