This self-laminating TZe-SL251 labeling tape has been primarily designed for the long-term reliable identification of Cat5e, Cat6, and Cat6a network cables with a diameter of 3.0 to 6.6 mm. It has been rigorously tested by Brother to ensure that you can print ID labels quickly and efficiently. This Brother TZe-SL251 black-and-white labeling tape is made with a special adhesive and materials that allow labels to be easily applied to cables.