The top shelf is small for large cat as described in description.  Cats like to nest, these are open,my mistake,thought my 3 legged cat would like the open but he wants a box, also there is no cushioning or padding so it like being on the floor.  Poor design all away around.  Too much hassle to return.  This was open box, had placed an order for one like but tried to cancel that within 10 
minutes but couldn't.  I think there are better options for the money.  See the metal bolts on the photo