The Milkies Freeze is a “first in, first out” breast milk storage system that fits easily in your freezer. Simply collect breast milk in any milk storage bag and place the bag on the metal quick-freeze tray located on top. Once the milk is frozen, slip the bag into the Freeze storage system through the slot at the top. When you’re ready to thaw a bag of breast milk for your little one, pull a bag from the bottom. That way you will always use your oldest milk first. Genius! Can store up to 60 ounces of breast milk.