This our brightest blue hair dye and it will certainly get hearts racing! This primary-color works with perfectly as a mixer with other shades to achieve the creative tone of your choice. However, it also works well with straight from the bottle for perfect bright blue hair. For the optimal results, we recommend lightening your hair to the level 9 or 10 (blonde) before use. It also suitable for level 8 (light brown) hair, however, results will be the tonal.