Philips Avent Natural First Flow nipples paired with Philips Avent Natural newborn baby bottles make a perfect set for gentle drinkers who may not have strong sucking power. First Flow nipples are made of soft, durable silicone, which is safe, odorless and flavorless. An ultra-soft, wide nipple promotes natural latch-on so you can easily combine breastfeeding and bottle feeding. It Mimics the feel of the breast and comforts your baby. The flexible spiral design combined with the comfort petals allows for a natural movement while your baby feeds. It was designed to reduce colic and discomfort by venting air away from your baby's tummy. Philips Avent Natural nipples should be used with the Philips Avent Natural bottle. When it's time, continue with the Natural Response Baby Bottle and nipple flow number 3 (SCY963/04) as your baby grows and strengthens the sucking power. However, we recommend that parents ultimately make decisions based on the observations of their baby.