The Tommee Tippee Closer to Nature Anti Colic Plus Bottles are safe, easy to use and effective, the ideal solution to bottle feed your baby from birth and through the months when a child is most likely to suffer from colic. Super-sensitive anti-colic valve and vent tube helps baby to feed without pause. Heat sensing tubes allows you to check milk temperature immediately. Has unique, easy lath-on teat shape and soft natural feel silicone teat. ExpirationThis product has no expiration date or the manufacturer has not provided an expiration date.