Heavy-duty galvanized steel fountain helps keep water cool. A constant water level is maintained in pan by vacuum. Top designed to prevent roosting. Tank has brass valve with rubber sealing washer for positive shut off.
I wish these did not leak so easily. I bought two since I like them, but I have to keep them outdoors because I don't want them leaking inside on the bedding. I was able to keep one level (I had to actually use a level) and put it on cement blocks. That one is not leaking. I use a lightbulb inside the cinder block to keep the water from freezing. So I gave this 4 stars because you can't heat up the plastic waterers to keep them from freezing.
I must admit, I have had a hard time using these as they always seem to need adjusted to stay level and not leak. Maybe it is just me, but I think they would work so much better if the base was taller, leaving more space between the top and the waterline.