Medela - Pump & Save Breastmilk Bags Medela Pump & Save Bags enable you to store breastmilk neatly and easily in the fridge or freezer. Simply express the milk label the bag and pop it in the fridge. Easy milk collection: Pump milk directly into the bag preventing milk loss Compact: Takes up less space than breastmilk bottles Reliable: Double-walled for safe long-term storage Pre-sterilized: very hygienic