The structure is really unstable and wobbly when you add on the extended pvc tube. The “connecting” bit is not strong enough and makes the entire tree wobble back and forth when kittens go up and down. The bottom also doesn’t have a grip so it slides around which makes the problem worst. I’ve had to screw the posts in again a few times cause they come loose. I guess this is what they mean by “you get what you paid for”. Will probably save up and get a higher quality one somewhere else in the future.