The Pure Blonde Booster Mask instantly conditions and neutralizes yellow tones, leaving hair feeling refreshed and looking clarified. The weekly, intensely conditioning formula contains an optimal amount of violet micropigments that correct yellow tones for a freshly colored look.Application: After shampooing, gently work into the hair, avoiding the scalp. Leave on for up to 3 minutes if the hair is bleached, up to 5 minutes if the hair is colored and up to 10 minutes if the hair is naturally blonde. Rinse thoroughly. Use once a week. These times are a guide only and should be halved on first application. Every hair reacts differently, so test a small section of your lightest hair before the first application. Wait at least two weeks after coloring, bleaching or perming your hair before using.