Size not good

I initially bought the small size which on the face of it was similar in size to my current dog bed. It is in fact tiny. The dimensions given include the very thick walls. This would be suitable for a cat or chihuahua. Pet Planet are going to get the internal dimensions added to the description. I next ordered a medium size which is still on the smaller size of the scale but will have to do. The bed itself does have an enclosed foam base and a separate foam filled cushion. The outer cover has a zip to remove for washing but the inner cushion doesn't.