Scientific Cutting Tools offers a comprehensive range of UN thread mills designed for precision machining of Unified National thread forms, including 2A/2B and 3A/3B classes. Whether you're cutting internal or external threads, our UN thread mills deliver consistent accuracy, clean finishes, and reliable performance. Choose from single profile or multitooth designs, with options including straight flute, staggered tooth, coolant through, and extended reach models. Manufactured from solid carbide, carbide tipped, or carbide head constructions, and available with optional AlTiN+ coating, our tools are built to handle demanding threading applications with efficiency and durability.