Fluorescent Green Semi-Permanent Hair Colours One of the most intoxicating colours in our collection, Fluorescent Green supercharges any style with an eye-popping luminosity that never goes unnoticed. For the most vivid results, we recommend applying to pre-lightened hair. The colour on the pot is a simulation of the colour on a level 10. Soft, silky hair never goes out of style. That’s why all our colours contain a conditioning formula that nourishes hair from first application.