The anti colic bottle is just one of the innovative developments from the mam design studio. Its vented base has small air holes and a silicone seal that allows for maximum air flow in while still preventing milk from leaking out. The vented base ensures controlled milk flow by balancing air pressure inside the bottle. Liquid is also pushed towards the nipple allowing it to retain its shape and preventing it from collapsing. All anti colic bottles use mams patented ultra soft silicone nipple. Transitioning from breast to bottle is simple because mam ultra soft silicone nipples feel most like moms breast. For babies that havee accustomed to feeding from a bottle, the babyfortably fits in babys hands, and similar to the anti colic bottle, features mams ultra soft silicone nipple. 0plusmonths, unisex colors. Bpa free, lead free, pvc free and phthalate free. One bottle and one slow flow nipple and cap included.