Keune So Pure Natural Balance Developer is the developer for Keune So Pure Color. It has extra stability, so the Hydrogen Peroxide percentage will remain the same, even at high temperatures. Only So Pure Color mixed with So Pure Color Developer will give the optimum result USAGE: The So Pure Color Developer is enriched with a color stabilizer, which guarantees optimum color stability ADVANTAGES: The main active ingredient in So Pure Color Developer is Hydrogen Peroxide. Hydrogen Peroxide is formed when water (H2O) picks up an extra oxygen atom (H2O + O = H2O2). The bond is not very stable and the oxygen will easily split off in an alkaline environment. The split-off oxygen develops the color pigments. When So Pure Developer 6%-20 vol. is used, some of the natural pigments will be fractured. In this way, the hair color is lightened. The higher the volume of Hydrogen Peroxide, the greater the amount of fractured natural Melanin. The Hydrogen Peroxide concentration determines the lightening power.