Four enclosed levels stack 49-in high on a footprint only 16-in square, so several cats get a den apiece without giving up a corner of the room. Each level opens through a 7.5-in hole and lays a bamboo mat on the floor, which stays cooler than plush when a cat settles in during summer. A large sisal board runs down one side for clawing. Every layer carries 33 lb, the covers pull off for washing, and the top perch lifts out entirely. The 22-lb frame is light enough to reposition alone.