SkinCeuticals Retinol 1.0 is a maximum strength night cream containing 1.0% pure retinol. This professional-grade skincare product is designed to refine skin texture and address signs of aging through its concentrated retinol formulation. As this is a high-concentration retinol product, it should be used only at night and introduced gradually into your skincare routine to allow skin to acclimate. Users should always apply sunscreen during daytime hours when using retinol products. This product is best suited for experienced retinol users who have already built up tolerance to lower concentrations.