1 Versus previous Koleston Perfect. Valid for Koleston Perfect with Pure Balance Technology.2 FOR PEOPLE NOT CURRENTLY ALLERGIC TO HAIR COLORANTS. Although the risk of developing new allergy is reduced, there remains a risk of allergic reaction that can be sever. Always ask your stylist to perform an allergy alert test 48h before each coloration. Strictly follow safety instructions and consult www.wella.com. If you have ever experienced an allergic reaction to hair colorants, you should not color. ME+ is present in specific shades of Pure Naturals, Rich Naturals, Vibrant Reds, Special Blonde and Deep Browns of the Koleston Perfect Brand.