Fits all Suavinex bottles (except Zero.ZeroTM bottle).Mimics the shape of the oral cavity. Simulates the dome shape formed by the palate and tongue: palate: convex top tongue: flat underside SLOW FLOW Lets a limited flow of liquid through. Indicated for milk feeds during the first few days of life or for water later on*. MEDIUM FLOW Lets all types of medium-density liquids through. Ideal for milk, juice or water. DENSE FLOW Lets all types of medium-density liquids through. Ideal for milk, juice or water.