The One Purple Shampoo from Kristin Ess Hair is a sulfate-free, highly-pigmented ultra-violet shampoo that instantly tones natural and color treated blondes and brunettes, removing unwanted yellow tones in hair while cleansing. If you like ashy or pastel lavender tones, you can use this every time you shampoo. If you like neutral tones, use it only when needed to cut brass. Once your hair is toned, pause on using this purple shampoo until you need it again. If you ever go overboard toning, shampoo with a clarifying shampoo and condition well. Use this with or without The One Purple Conditioner. It’s safe for keratin treated hair and is free of sulfates, parabens, phthalates + silicones.