Neutrogena® Stubborn Blackheads Serum is the new way to fight blackheads. Put on and leave on to melt away blackheads, visibly clearing clogged pores and helping to eliminate stubborn acne in as little as 3 days. Designed for oily, acne-prone skin, this oil-free face serum visibly clears clogged pores to help eliminate stubborn breakouts and blackheads.