Acidifier based on citric acid, which, when added to the colour mixture, lowers the pH value and transforms the Technofruit Color permanent colouring cream into a colouring cream with a tone-on-tone effect. It is also ideal for first-time colour application on natural hair and for colour recovery and toning services. The product is an IRRITANT, please carefully read the warnings provided. Sunburn Alert: this product contains an alpha hydroxy acid (AHA) that may increase your skin's sensitivity to the sun and particularly of sunburn. Use a sunscreen, wear protective clothing, and limit sun exposure while using this product and for a ween afterwards.