COSRX The Niacinamide 15 Serum 20mlTotal acne care with 15% niacinamide Highly concentrated serum that combines the maximum concentration of niacinamide with optimal ratios of synergistic ingredients for total acne control. *Non comedogenic tested doesnt clog the pores. Clinical Results in 4 weeks Suitable for acne prone skin use (Non comedogenic) 45. 27% improvement of activated sebaceous glands 48. 07% improvement of oil synthesis amount 42. 72% improvement of number of blackheads