Dr. Brown's Narrow Neck Breastmilk Collection Bottles 4 Pack (White & Blue)Dr. Brown's Breastmilk Collection Bottles Streamline the pumping and storage process with Dr. Brown's Breastmilk Collection bottles, designed to work seamlessly with a variety of breast pumps. Each bottle features clear volume markings and can hold up to 4 oz 120 ml of breast milk. Easily transition to feeding by attaching Dr. Brown's bottle parts and nipple (sold separately) for hassle free use.