This all wood hand made, cage top, play set is approx. 23" tall, at the tallest point. The other posts are 19", 18", and 14" tall. The outside dimensions are approx. 18" x 21". The perches are 7/8" and 3/4" in diameters, and has tree caps on the ends to chew on, (orders from Canada and Australia will have large wood dowels for caps ,instead of tree caps) . It's all made of safe pine wood with hard wood dowel perches. It has a swing, wood chew toys on solid rings with safe sisal rope, and an 18" ladder. When the toys are chewed off the rings, just add more. It mounts easily to the cage top with wing nuts and washers. This gym is a very good money saving set. This gym is for large birds like amazons, african greys, mini macaws, and other large birds. It is a large and busy set, and this gym will give your pet or pets many, many hours of fun and pleasure. This item will be shipped broken down for cheaper and easier shipping. All you will have to do is assemble 4 dowels and 2 steps to the posts with the screws provided, or a drop of glue. The holes are pre drilled and recessed for safety.