Glow Zero is ammonia-free permanent coloring, p-Phenylenediamine and Gluten, ideal for clients with ammonia intolerance and skin sensitivities who do not want to give up ultra-professional color results. It is dermatologically tested and specific tests ensure low heavy metal content (Nickel, Cobalt and Chromium Tested). Glow Zero has a researched formula in perfect balance between precious natural actives and high-purity quality pigments to ensure extraordinary cosmeticity. There are 65 shades that can be mixed together and can also be used in combination with other Cotril colors. Dilution 1:1 and 1:2 for Superblondes.