This thing is terrible. The cardboard doesn’t lock into the base so if you stand it vertically, the cats just rip the thing out, and if it’s horizontal you get to listen to them repeatedly lift the heavy cardboard up and slam it back down into the base. 
The base itself where you connect the top wooden part which connects to the stand is only connected by the smallest shreds of Velcro (see picture) which of course don’t line up properly so that’s not terribly secure either. 
Skip it. Find something that locks into place. What a horrible design.