This is a reversible pet heater that can be used at high (approx. 39°C) and low (32°C) temperatures. It can be used by placing it on the floor or attaching it to the cage bars. Simple fasteners (cable ties) for attaching to the bars are also included. Since it is not made of cloth, you can wipe it clean whenever it gets dirty. This is a size S, so how about it for small animals? Size: Approx. Width 24.0 x Depth 16.5 x Thickness 1.5 (cm) Although it is a new, unused item, please understand that it has been stored at home.