0WellaWella Multi-Blonde PowderMixing Recommendation Mix with Koleston Perfect Crème Developer 1.9% or 4% in a non-metallic bowl. Mix in a ratio of 1:1.5 up to 1:2, e.g. 30 g powder + 45 ml Koleston Perfect Crème Developer. If there is contact with... November 10, 2015Read more