La Roche-Posay Effaclar Ultra Concentrated Anti-imperfection Serum is a concentrate of exfoliating acids combined with soothing niacinamide, that targets blackheads, pimples, marks and visible pores. This no-rinse formula leaves the skin refined and purified. The first ultra sensorial La Roche-Posay care to combine such a high concentration of synergic actives: 3 keratolytic acids to reduce imperfections and marks + niacinamide & Thermal spring water for a soothing and anti-redness effect. Perfect balance between peeling and soothing actions, the serum unclogs pores and corrects persistent imperfections and marks day after day.