I have had ferrets for over 9 years and have always used glass water bottles in their cages. I have never had a leak. They clean beautifully and hang on a metal holder that is permanently attached to the cage (none of those annoying wire loops!). They sell them online at That Pet Place and they are presently listed as $16.99. http://www.thatpetplace.com/pet/prod/200793/product.web [Posted in FML 6503]