Took forever to put together between me and a friend...and no matter what we did, zip ties or no, it wouldn't line up properly or stay together.
Panels will pop out in certain places and pieces, which I made doubly sure to secure with additional zip ties and Velcro ties pop out on their own. 
Before posting this review, my poor cat was resting on the top layer for about a good 5 to 10 minutes and a panel above him popped out, taking out a few panels below it. I know for a fact it wasn't because he was too heavy to be up there, he's a small and lean cat, 8 pounds at the very most. 
It scared the ever-living daylights out of him and I'm glad he wasn't hurt but he very well could have been due to the shoddy design and mismeasurements of this product.
Avoid this Catio if you can help it.