The Store n" FeedTM Storage Container"s durable leak-proof construction will stand up to every day use. It is also multi-functional as it transforms, attaching to the SoftFlexTM Breast Pump and NûbyTM Natural TouchTM nipple. Simply remove the container top and replace with the NûbyTM fixture of you choice (not included). It also works great for your child"s dry snacks. Made from BPA FREE clear, break-resistant plastic. Graduated in both ounces and ml. Includes 4 Storage Bases and 4 Lids.