Stimulates Oral and Tooth Development, With Cap for More Hygiene and Safety, Soft, Flexible and Ergonomic as Mother's Nipple, High Quality Silicone Teat Stretchy like mom’s breast when baby suction. Stimulates the oral and tooth development. Will not press baby’s face while baby sleeping. Ergonomic as mother's nipple, soft and flexible. Stretchy teat gives a natural and security feeling for baby. Out rim is soft, so it does not press baby's face while sleeping.