Simply attach Hegen PCTO™ Manual Breast Pump Module and/or Hegen PCTO™ Standard / Wide Neck Adapter to express into the storage container, then swap the pump with a Hegen PCTO™ Breast Milk Storage Lid, instantly converting it into an air-tight and secured storage container for storage in the chiller or a storage bag. To feed, simply reheat to desired temperature and change the lid to a feeding lid for convenience and zero transfer of milk.