At Scientific Cutting Tools (SCT), we take pride in crafting high-quality, American-made cutting tools for industries that demand precision. Our UNJ external thread mills, made from premium sub-micron carbide, are designed for high-strength applications such as aerospace and defense. We offer two external UNJ thread cutting options as seen below: the Partial Profile SPTM EXJ and the Full Profile EXJ Thread Mill—both engineered to conform to aerospace standard AS8879. These tools provide enhanced fatigue resistance and superior thread quality, ensuring optimal performance in demanding environments. Explore our range of UNJ external thread mills for reliable and consistent machining results.