Smooth treatment mask for fine hair, one of a 4-pack has been used, so this is a listing for 3 packs. - Brand: milbon - Product Name: Smooth No.4 Weekly Booster Fine Hair Masque - Contents: 9g x 3 - Purpose: Treatment - Target: Fine hair When I had a milbon treatment at a hair salon, I received this for home care, which is supposed to have the same effect. It seems best to let it penetrate for about 15 minutes, but I have atopic dermatitis and dry skin, so my dermatologist told me to stay in the bathtub for less than 5 minutes. Waiting for 15 minutes in the shower alone was difficult, so I used it once and the rest are left. It's for 3 uses, but it's not a set of 4, and I was told to use it about once every two weeks. It seems to be a salon-exclusive product. I'm selling it because I don't use it. I have super long hair, down to my waist, but after the treatment, I combed my hair, put it in a shower cap, waited 15 minutes in the bathtub, and then rinsed it again. My hair turned out smooth, shiny, and silky, just like after a salon visit. Frizz is also greatly reduced. Please give it a try. Thank you for looking.