Natural Fast Flow Nipple is designed for babies at least 6 months old and offer a fast flow. These nipples are made of soft, durable silicone, which is odorless, flavorless, and BPA free. The nipples can be sterilized in any steam sterilizer, boiled for five minutes, or washed in the dishwasher. A wide breast-shape nipple promotes natural latch-on so you can easily combine breastfeeding and bottle feeding. Our flexible nipple design combined with the comfort petals allows for a natural movement while baby feeds. Unique Airflex vent technology is integrated into the nipple and is designed to reduce colic and discomfort by venting air away from your baby's tummy.