The color that changes everything, with ME+ technology. Pure, balanced color results with natural depth and shine. ME+ reduces the risk of developing a new allergy to hair dyes for individuals who do not have an allergic reaction to hair coloring products. While the risk of developing a new allergy is minimized, the risk of an allergic reaction, which can be severe, still exists. Always ask your stylist to perform an allergy test 48 hours before any coloring. ME+ is included in specific shades of the Pure Naturals, Rich Naturals, Vibrant Reds, Special Blondes, and Deep Browns ranges of the Koleston Perfect brand.