Lansinoh's #1 selling breastmilk storage bags are ideal for storing, freezing and protecting precious breastmilk. Built super strong, Lansinoh's breastmilk freezer bags come with a double zipper seal to prevent leakage and reinforced double sealed side seams for ultimate protection. Presterilized for safe storage plus BPA and BPS free. Easy to use and saves time by pumping directly into the bag.