Extra-Small = $8.50 Fits Mice
Small = $10.50 Fits Mice and Young Rats
Medium = $13.50 Fits Mice and Rats
Large = $15.50 Fits Rats and Young Chinchillas
Extra-Large = $17.50 Fits Rats and Chinchillas
It has a nice flat top bunk then underneath that it has a tunnel for your little critters to hide in and feel safe.