This is by far the best Shampoo and Conditioner for hair extensions on the market. It repairs your natural hair as well as your human hair extensions. A coating of silicone is put on the hair extensions when they are packaged for sale. After a few washes, the silicone washes off the hair extensions. Joico Silk Result Shampoo and Conditioner has silicone, keratin protein, silk polymers, and hydrators that keep hair extensions better than new. I use it on all my hair extension customers to give them the best result possible. Each liter bottle contains 33.8 ounces