After intensive testing the new Koleston Perfect range provides a natural depth and shine; while causing less hair damage than traditional tints. With a simple 1:1 mixing ratio, proven 100% grey coverage and up to 5 levels of lift! While ME+ technology massively reduces the risk of developing an allergic reaction to these colours, it is not for use by people allergic to hair colourants. Wella has developed a high-quality tint, that delivers vibrant colours and total coverage!