Kiehl's Ultra Pure High-Potency Serum 5.0% Niacinamide Facial Serum 30mlWhat it is: A concentrated facial serum formulated with just 10 ingredients to help visibly reduce oil and minimise the look of imperfections. Who it's for: Oily skin and sensitive skin types. What it does: With 5% Niacinamide, this serum is formulated with just 10 ingredients to help visibly reduce excess oil and minimise the look of redness and imperfections. Free of fragrance and colourants, this concentrated serum is minimally formulated for skin