The Wella Professional Welloxon Perfect 9% 30 Vol Crème Developer (1000ml) is specifically designed to be used with the Koleston Perfect Me+ range; the combination is designed to create a pure and balance, high-shine colour result. The consistency of this crème developer promotes much easier and faster mixing of hair dyes as well as easy rinsing once the colour has developed. It is designed to allow for more precise application and allows high level foil adhesion. The stronger the developer, the harsher it can be on your hair. This 9% crème developer is a perfect strength for a permanent, no-lift colour and will do minimal damage to the natural hair.