Medela polypropylene breast milk bottles are made without BPA, designed to retain breast milk's beneficial properties. Compatible with all Medela breast pumps, so you can pump, store and feed with one container. Great for long term storage. Dishwasher safe. Measure the exact amount of milk you're pumping with the ounce and millimeter markers. Screw on lids for leak proof storage, travel and freezing. Travel cap keeps nipple clean. Includes (3) bottles; (3) wide based medium-flow nipples; (3) collars, solid lids & caps. Plastic bottles and component parts become brittle when frozen and may break when dropped. Also, bottles and component parts may become damaged if mishandled, e.g. dropped, over-tightened, or knocked over. Take appropriate care in handling bottles and components.