They allow freshly expressed breast milk to be kept airtight in the fridge or freezer, they are disposable, the bags are pre-sterilised, so there is no need to wash them beforehand, they are very practical if you have little space, as they can be stacked on top of each other, their wide base allows them to stand upright, the side spout allows you to pour the milk comfortably into the bottle in a way that is easy to clean.The wide base allows them to stand upright, the side spout allows milk to be poured hygienically into the bottle, preventing milk loss or spillage, there is space for you to write down the date and amount of extraction and they have a zip closure for easy opening and closing. They contain 25 units, each with a capacity of approximately 180 ml.