NOT SUITABLE FOR GERBILS OR HAMSTERS
Gerbils LOVE to chew, and will chew the plastic base in no time - they also LOVE to burrow and need at least 7inches of bedding all the way round - which this cage doesn't provide. Hamsters can climb, but aren't good at it and can hurt themselves badly, so this tall cage isn't good for them - they also need at least 6 inches of bedding. I don't believe it is big enough for mice, but I haven't done enough research on that. The size is good for three rats though