Maymom Milk Storage Bottles for Medela Breast Pumps is a set of 8 milk collection and storage bottles. You can pump directly into these bottles with Medela breast pumps and they are also compatible with Maymom narrow-neck breast shields. Includes 8x collection & storage bottles (150ml) Compatible with Medela Flex breast pumps, Medela breast pumps, Maymom narrow-neck breast shields Narrow-neck Sealing ring included to provide 100% leak proof travel and storage. Measurement is embeded, so no chance for faded markings. Heavy duty PP, food-contact grade, BPA free Dishwasher toprack safe Steam safe for sterilization Do not UV sterilize Recommended for 0+ months.