4-Pack sealed breast milk collection and storage bottle with lid - size 5 oz/ 150 ml.;Bottles are compatible with all Medela breast pumps. Milk can be expressed and pumped directly into the container.;Easy to read measurement in ounces (oz.) and millimeters (mm). Reusable bottles. Resistant to scratches, cracking and splintering.;Bottles fit Medela container stand. Dishwasher and microwave safe.;Screw-on lid for leak-proof seal - ideal for storing breast milk in refrigerator or freezer. Special polypropylene plastic retains breast milk's beneficial properties - safe & hygienic method for long-term breast milk storage.