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Title: Convenient doesn't quite colapse like it should
Review: I have been using those for months and will keep using them. They are convenient because it is easy to prep a per-sterilized bottle without having to worry about cleaning bottles. I usually rotate with 4 nipples so I always have at least one clean to put on the bottle and it is ready.The bags don't seem to collapse as the milk is drunk. This might be more an issue with the bottle itself than the drop-in.First few times I wasn't careful in positioning the drop in and ending up pouring the most of the milk on baby due to a bad leak. After doing that twice I was more careful in positioning the drop-in.Conclusion it is a great idea, time saver on cleaning.
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