The delivery was spot on but I was initially disappointed and a little concerned when I opened the package. The Petporte box containing the cat flap just literally fell apart. It was well used to say the least (this was not the fault of the delivery company). Not sure why. Still I wasn't buying the box!! A product parts listing would help. I wasn't sure if any parts were missing. At least that ensured I read all the instructions. Initially it looked like the fitting would be tricky, especially as I was replacing an existing cat flap, but it wasn't. The instructions were very good, and it works well under test. As yet the cat is very wary of entering - we are still at the training stage. But the purpose of replacing the cat flap was to keep out a troublesome black cat that was getting fatter by the day, eating what we were providing for our cat. The cat flap has stopped that.