Comments: I have used this water bottle for quite awhile and have many of them for my mouse breeding cages. However, This last group I got ( 5 bottles) was bad - every single one of them leaked badly and I had to return them. I think maybe they used a lighter weight ball bearing in the tube, which let water leak out. It has hurt my previous confidence in the product badly as I went to another store, bought 4 more, and they leaked as well. I have never had this problem before with these water bottles. I will probably change to a different water bottle since the manufacturer has evidently changed the way they are making these - which is unfortunate because they fit perfectly in my Reptile Ranch cages.