Formerly this was called the Haberman Feeder - For use in cases of special feeding problems, such as cleft lip or palate. It has a one way valve so that you can manually compress the extended teat and this will help the flow go into the baby's mouth for those that are not able to provide a seal to get suction to draw it out themselves. If you are unsure about your need for a Haberman Feeder, please e-mail or call and ask for PJ at 888-398-7987. There are three options - a regular with an 80ml bottle for most full term babies, a regular with a 150ml/5oz bottle for a little older baby that is needing more at a feed and a mini size for preterm babies. You can get extra teats for each size here also.