KatWALLks makes a variety of perches, platforms and walkways that mount directly to the wall to create more vertical space for your cat without the addition of a freestanding cat tree. The Balcony is 17 1/2 inches square. It's made of oak, with a replaceable carpet (choose from 35 carpet colors). Like all of KatWALLks' feline furniture, the Balcony can be mounted directly on drywall (the Balcony's corner mount is supported by corner studs) and all the hardware you need to mount it, including anchors and the right drill and screwdriver bits, are included. The Balcony also comes with detailed mounting instructions.