These are great because they go from attaching 2 the Medela pump 2 the freezer 2 attaching a nipple. Problems are that after a couple of months the nipple would collapse as baby would drink. Maybe the next size nipple would work but baby was still only taking 4 oz so a bigger bottle wasn't needed. Even though I always hand washed them, the markings on the side are rubbing off. If supplementing w/ formula it is almost impossible 2 dump a scoop of formula in because of the narrow opening.
Reviewed by: Abby Dupuis from Columbus, WI.