I purchased this one because of the top. Previously I bought the smaller Iris pen with no top and my Yorkie puppy managed to scale the sides and get out. Then I bought the large one with the mesh top and she figured out how to get the top off on one side, climb up the top as it was then on a slant and get out. I was afraid she would get hurt jumping down. I tried putting zip ties on the top because the Velcro did no good with my determined escape artist. Well that worked for a while until she decided to just put a hole in it, jump and pull herself up to freedom! Iris does not provide replacement top sadly so I decided to get one with a metal top but hoping to find one with the same kind of detachable bottom since I really loved this feature. Thankfully Iris has such a thing! Unfortunately the door doesn't slide to the side but on the positive side, the top clips on so it is removable and you can just open one half for access if you want. Now mind you, my Yorkie now is 10 months and barely 4 lbs so she did all this when she was a lot smaller! I work in the office just 2 days a week, so she is not in there every day. I do have it set up so her washable pee pads are in there and her potty box. She also eats in there too. I just leave the door open when I am home and she know just where to go. It seems to be working out well and have had it for a few months. The clips for the bottom seem sturdy, although when you pick the pen up, it is heavy. But worth it so I can put the edges of the potty pads in the grove so the pens holds the edges in place.I purchased this for my rabbit and it's absolutely perfect!! He loves it and has plenty of room to do laps inside of it. I love the fact that the top flips open which makes it so easy for me to clean the inside and to feed him. I love the fact that it's not a grid like most crates are because he doesn't try to climb it. As far as dogs go, I would only trust this with a small calm dog. If you have a dog who tries to escape his enclosure, this might not work. And I can't see this working for bigger dogs despite the nice size of this crate just because it doesn't seem to be tough and extremely sturdy. But it's perfect for my bunny!Cage semi does what I need it just doesn't have the top of the cage.Was not what I was looking forI love the versatility of this pen....the top folds over for easy access or you can take it off, the pin on the door to hold it open or closed is great! Easy to take apart and store when not in use also....just a great pen.Did not have all pieces I am upsetPerfect for a free roaming rabbit!! Tito the bunny loves, spends his time in there all the time and it gives us peace of mind if a stranger comes over. We had an incident where someone brought their dog into our apartment without asking and our bunny got hurt. Now we can lock the door if someone comes over and not worry about it. Not sure I could trust a particularly naughty pup in there for an extended time because the clips at the bottom are a little flimsy. Would recommend!!Great cage for my living area. I use it for my young puppies or my moms with newborn litters.I like the dimensions. It's a big cage, idea for smaller breeds. I think a medium to large breed puppy could bust out of it pretty easily.There is no top panel in the package, which does not match to the product image. So disappointed to return it and waiting for refund.It’s very sturdy, easy to put together & the perfect size for a growing female husky. True to size!arrived brokenWorked out perfectly. I love that the top opens, so much easier to access dog and for cleaning.