Wella Koleston Perfect Permanent Hair Color 0/33 Intense Dark Brown 2 Ounce 60 Milliliters Wella Koleston perfect is one among the hair colors with ME+ technology. This offers pure, balanced color results with natural depth and shine. The unique characteristic of ME+ technology is that it is very likely to develop an allergy to the client. It has over 110 shades of intense vibrant color. Offers long-lasting grey coverage and up to 5 levels of lift. Simple 1:1 mixing ratio. *This is a professional product and should be used only by a trained individual. Seller is not liable for any adverse outcome resulting from the use of this product.