La Roche Posay Effaclar Mat is an oil-control moisturizer that combats shine and reduces pore size in oily acne-prone skin. Effaclar Mat is formulated with Sebulyse which helps to mattify skin and tighten pores. Sebulyse sebo-regulating efficacy is clinically proven to be superior to Zinc, the standard active ingredient used to address oily skin concerns.