The towel is made of 50% nylon/50% polyester and is latex-free, lightweight, soft and breathable. When wet, it cools for up to 2 hours and when dry it absorbs sweat. To activate, simply soak the towel, ring out any excess water and snap (to re-activate, re-soak and snap). It comes inserted in a BPA free, 20 oz. water bottle with flip up lid.