Masks ek tarah ke topical formulations hote hain jo clay, sheet, cream, gel ya peel-off type ke ho sakte hain. Inhe skin par lagakar kuch time ke liye rakhte hain - kuch ko rinse off karna padta hai aur kuch leave-on hote hain. Ye concentrated actives aur hydration ko deliver karte hain aur skin ka oil absorption improve karte hain. Basically ye ek delivery format hai jo skin ko deeply treat karta hai.