bought for my chinchillas to have  something to jump and play on and they love it.  the top stair is a little wobbly though still sturdy enough for my cats and 20 pound puppies to also climb.it  is also good if you have to put your cats dishes or litter box up on a dresser or table as they can climb this instead of having to jump .probably would not buy for a larger dog but is great for smaller pets 30ish pounds or under