Review on Endura Flap Pet Door: Single Flap Extra Insulated Cold Weather Dog Door, Aluminum Indoor/Outdoor Door | Easy Install | Sizes: Small, Medium, Large, Extra Large | White, Tan, Black by Carl Ferguson

I installed it myself and it took a few hours. For me the hardest part was screwing the front to the back. Once the screw is in the hole, getting it out will be a big problem. (Initially I used the wrong screw size). Mastered removing a screw with a small flat head and a paint can cap remover. Then, once I had the correct screws, the back panel just WILL NOT hook the screw. I had to leave and come back the next day to try again. It would be great if the manufacturer found a way to route the screw to the correct location on the back. But now that the job is done. I JUST LOVE IT! I'm still working with dogs to get used to it.