Please note: This item requires a compatible Clinique iD Base To make use of. A revolution in skincare technology; the Clinique iD is a unique two-part remedy that lets you mix’n’match, combining this cartridge with a compatible Clinique iD base, creating a remedy tailored for your skin’s needs. Custom-Blend Chemistry Technology ensures that the active ingredients of both the bottom and the cartridge are delivered to the outside with each pump. Ingredient potency is maintained. The Active Cartridge Listen for Irritation offers a soothing effect for the outside, calming the outside with a special lactobacillus probiotic ferment. To make use of: Insert the cartridge into a Clinique iD base ensuring the cartridge is held firmly in place. Apply mornings and/or evenings to the cleansed face.