Designed to feed baby naturally these philips avent bottles have large teats which mimic the shape of the breast helping baby to learn to alternate between breastfeeding and bottles ergonomically shaped for extra comfort soft flexible teats and refined anti colic valves ensure air enters the bottle and not babys tummy set of 2 available in 4 sizes 1 1 hole soft flow suitable from birth 2 2 holes slow flow suitable from 1 month 3 3 holes average flow suitable from 3 months