Philips AVENT SCF655/27 Natural Variable Flow Nipple is designed to make it easy to combine breast and bottle feeding. The wide, breast-shape and unique comfort petals make the nipple softer and more flexible to promote natural latch-on. The petals also reinforce the shape of the nipple to prevent it from collapsing in baby's mouth so your baby can feed contentedly and without interruption. The nipple's shape encourages the same tongue movements suckling babies use when breastfeeding, so transition between the two is less confusing for your baby. The Variable Flow Nipple is designed for babies at least 3 months old. Featuring a slot hole design, the Variable Flow Nipple allows you to change the flow of milk, provides an extra fast flow and accommodates thicker liquids. Simply turn the bottle to line up the I, II or III marking with your baby's nose to choose between slow, medium and fast flow. The Natural nipple features twin anti-colic valves that work to make feeding more comfortable for babies. During feeding, the valves release air back into the bottle rather than into your baby's tummy, which reduces colic and discomfort. These nipples are made of soft, durable silicone, which is odorless and flavorless. The nipples can be sterilized in any Philips AVENT steam sterilizer, boiled for five minutes, or washed in the dishwasher.