Petmaker Portable Pop Up Pet Play Pen with Carrying Bag

We love this pen for our kitties. As we got it for using in the house. The top unzips and the kittens love getting on top of it to lay down on the solid side like a hammock. It keeps the sand in the pen and it is easy to clean, as we just take everything out of the pen and turn it up-side-down to spray clean the inside of it and let it dry. Only thing is that when we first got it we had to take it outside to air it out for the day because it had a chemical smell that smelled a little like gas. But whatever it was didn't bother our cats as we had a hard time with getting them out off the pen so that we can take it outside to air it out. I have been thinking about getting a second one, and it is worth the price of this pen. As I have seen some that you can unzip the top and the bottom, but if you are going to also use this inside. This is the best choice.