The Avent PES Bottle is clinically proven to reduce colic. The anti-colic valve flexes to allow air into the bottle, reducing colic. The soft, naturally shaped nipple makes it easier to combine breast and bottle feeding. The bottle is made from PES, a BPA-free material with a natural honey-colored tint. Features: * Reduces colic * Less air in baby's tummy * Easy to combine breast and bottle feeding * BPA-free