Drinking Water Pack for Backpacks (Bite Valve) (2-liter) 2 liter capacity, Made of FDA safe material Drinking water safe. 100% odorless, tasteless polyurethane bladder to ensure water quality and taste Replacement bladder for most hydration backpacks or can be used with many other back packs and pouches Easy to clean hose and bladder Water consumption controlled by bite valve, leak proof cap