Philips Avent Glass Natural bottle with the Natural Response nipple lets baby control the pace of the milk, like they do when breastfeeding. This Natural Philips Avent baby bottle is made of premium quality borosilicate glass, a BPA free material; It is heat and thermal shock resistant, so it can be safely stored in the fridge or warmed and is easy to wash and sterilize. Easy to combine breast and bottle feeding with a wide breast-shaped nipple with a soft feel that mimics the shape and feel of a breast No-drip nipple design helps prevent lost milk from the tip of the baby bottle, giving you peace of mind; Bottle Nipple comes in Flow 3 Anti-colic valve is designed to reduce colic and discomfort by sending air away from your baby's tummy What's in the box: 4 8oz Natural Glass bottle with Flow 3 Natural Response nipple.