Unique smooth flow bottle nipple design allows baby to control the speed of the flow of milk for colicfree feeding SafeTemp Indication thermometer icon on bottle changes color when milk is too hot Accepted by 98 of babies based on market research 2019 tested with 145 bottle users Bottle nipple mimics the shape of moms nursing nipple during breastfeeding for a smooth transition from breast to bottle and back Wide neck bottle is easy to clean and dishwasher safe