When I feel my hormonal acne start to flare up, this is the best mask out there for it. It says to leave on for 10-20. I leave it on for 20+. I usually use it after cleansing balm, then follow with this during the nighttime as it contains aha’s and they don’t always land the best with my skin during the day. This usually costs 15 elsewhere And is rarely under 8. Lasts several months with daily/weekly use.