This hair treatment is formulated for “dry and sensitised hair.” This product was recommended to me by my hair stylist to nourish my dry hair. Of course, the salon price was ridiculous so I went searching for a -as I like to call it- more cost efficient vendor. The best price I found for the Kerastase Nutritive Aqua-oleum was at one of my favorite stores, http://www.beautyvice.com/. Anyhow, I love it. The box comes with 4 bottles and a spray applicator. The directions say to spray it on, section by section; massage the product through your hair; comb each section of hair; then rinse thoroughly. Well, it worked like a charm. I love how my hair turned out. I’m still not sure how often I’m supposed to use it, but I guess I’ll wing it. Thumbs up on this one!