Insulated Bags are compatible with the 500ml Z & Co Pouches. They are designed to assist in keeping formula cold or warm. They are stylish, easy to use and clean. The Insulated Bags have ring at the top so the bag can be hung and a large opening at the bottom to allow easy access for the formula. Depending on the size of your ice brick, the bag may have room to accommodate this, though this is not guaranteed.