Wella Koleston Supreme Hair Color 4/0 Medium Brown offers 100% grey coverage and fights the 7 signs of damaged hair. Its oil-infused elixir provides moisture at every step for luminous, moisturized, and vibrant hair. Delicate floral scent Plex technology Moisture built into every step Oil-infused elixir 100% grey coverage Anti-damage technology Luxurious oil color cream Intense, moisturized, and luminous color Key Components: Hair Dye (Contains Ammonia, Resorcinol, Phenylenediamines, or derivatives); Developer (Contains Hydrogen Peroxide); Conditioning Sachet.Wella: Innovators in professional hair color and care solutions.Mix Koleston Perfect Color With Oxidant Of 4, 6, 9 Or 12%. Apply On Dry, Unwashed Hair.Hair Colorant Warnings: Must perform a patch allergy test 48 hours before use. Severe allergic reactions possible. Contains Ammonia and Hydrogen Peroxide.