My holy grail benzoyl peroxide treatment. Ignore the “mask” and other nonsense here. This is a bpo treatment. You can leave it on for short contact therapy (like a mask), use as a spot treatment, or if your skin is accustomed to it, as an overnight treatment. Studies have shown 2.5% bpo to be as effective as 10% without the irritation so no need to search out the higher percentages, this will do. This is also fungal acne safe and has a minimal ingredient list. Perfect for what it is.