This was a replacement of the tower I purchased 3 years ago. This one is not as sturdy as the one previously purchased. The assembly was the same. It was very easy to put together. The cats are still getting used to it due to the micro feel instead of their previous one of carpet texture. I chose this one due to more hiding options, and we have the space for the size of this unit. I posted only 2 stars because of the cost of this unit and how it rocks when a cat is on it. They are uncertain of the tower because of the movement.