SUPER STRONG- Store, protect, and freeze precious breast milk with these breast milk storing bagsPRESTERILIZED- Our milk storage bags have a double zipper seal to prevent leaksREINFORCED SEAM- Double sealed side seams for super strong breast milk collecting bagsPUMP DIRECTLY- Breast milk storage bags can be pumped directly into with Lansinoh pumps or used with our adapter on most major pump brands#1 SELLING IN US- Lansinoh is the #1 seller of breastfeeding supplies in the US, as well as the top selling breast milk bags