I bought this with a Life Stage Fold & Carry Double-Door Dog Crate and they work together very well.  It's very easy to set up.  When I want to keep our 10-wk old Lab puppy in a Crate inside of our house, I simply attach this Pen so she has more room to walk around.  Then, I can easily detach a Pen from a Crate and carry it outside to our backyard.  It's well-built, and I like its double-lock door and it comes with 8 plastic floor protectors that you can attach. I have only used this product for one day, but I already love it!