The Natural Response silicone nipples in a 4-pack from Avent mimic the feeling of breastfeeding to facilitate the combination of breastfeeding and bottle feeding. The opening of the nipples is designed to release milk only when your baby is actively drinking. This allows your baby to suck, swallow, and breathe at their own pace—just like breastfeeding. The particularly soft texture and wide design of the nipple resemble the sensation of the maternal breast. The anti-colic system reduces the risk of your baby swallowing air while drinking, thus preventing colic and discomfort. The optimal flow of food depends on how quickly or slowly your baby drinks. A slow flow is suitable for active, fast drinkers, while a fast flow is ideal for slow and steady drinkers. The opening of the stage 4 nipples allows for a controlled, medium flow and is suitable for babies from 3 months old. Package includes: 4 silicone Natural Response nipples – stage 4.