Stage 1: 0-6 months, slower flow. Clear bottle with silicone nipple. Johnson's Healthflow has a patented angled bottle design that helps promote healthy feeding and features a silicone nipple designed for breastfeeding babies. Helps Prevent Ear Infections: Johnson's Healthflow angled design makes it easier to feed babies in the semi-upright position, which pediatricians recommend because they believe it may reduce the flow of liquid to the middle ear and the chance of ear infections. Helps Reduce Air: Johnson's Healthflow angled design keeps the nipple filled with liquid instead of air throughout the feeding. Less air in the nipple means baby may swallow less air and experiences more comfortable feeding. Designed for Breastfeeding Babies: The Johnson's Healthflow silicone nipple is shaped to make feeding easy for your baby. The nipple has a rounded tip to help your baby latch on, and its base conforms to baby's mouth to help seal out air. The nipple is made from silicone, the softest material available to respond to your baby's sucking action. The Johnson's Healthflow Stage 1 nipple is specially designed for younger babies. It has a smaller opening to help prevent your infant from receiving too much liquid. Also available in Stage 2, with a faster flow for older babies.