Hyper Acid 4 (AHA BHA PHA LAH) 30 Serum 20ml, IsntreePRODUCT INFORMATION New concept AHA, BHA, PHA and LHA 30% rinse off serum, designed for intensive exfoliation after just one minute of use. Key ingredients: Optimized 30% ACID 4 Formulation (AHA 15. 3%, BHA 0. 1%, PHA 14. 61%, LHA 0. 01%) This is a high performance rinse off exfoliant that helps smooth the skin texture and even out the skin tone by gently removing the dead skin cells and reducing the excess sebum production. 1 minute rinse off serum