The first and only Non-Drip™ nipple (patent pending) is uniquely designed to help prevent drips and spills. With a pressure sensitive valve feature safely built right into the nipple, fluid only flows out of the nipple with your baby's sucking actions. With your baby's comfort in mind an anti-colic feature was designed into the nipple helping to prevent ingestion of air by baby. The offset surfaces of the nipple help to massage and soothe baby's achy gums during teething. The bottle is made of clear, break-resistant plastic that is BPA free. Can be boiled and is top rack dishwasher safe.