This is a RPM 2.5mm Allen Driver. To keep up with customer demands, RPM decided to add this straight tip Allen driver to the current line of hex drivers. The 2.5mm straight tip driver is color coded black, and the size is molded directly into the handle for easy identification. Like all of the RPM Allen drivers, RPM uses only the highest quality tool steels to produce our hex tips. The tips are molded directly into the handle so there is no assembly required.