I did lots of research and tried two others but this is by far the best. A lot of the indoor pens are dark and the puppy can't see out.  He was not happy!  But when I used this one he was content and played. I think because he can see his surroundings. The door is great too for him to walk in and out of when he wants. I think it helped him get used to it. Great height too!! Will still work as he grows