My Dad came up to help me install an opening in the basement door for my 2 cats to be able to visit the litter box without leaving a door open. We took the door off its hinges and carefully measured - not once, not twice but THREE times !! We were thrilled that the template worked out so well and the cutting was so easy. We put the plastic framework in the opening and then hauled the door back up the stairs to re-attach it to the hinges. Imagine the look on our faces when we realized we had cut the opening in the top half of the door instead of the bottom !!! The standing joke around here is that I must have flying cats -- I found a cute photo of a cat and added some feathers to it to cover up the stupid hole in the top of the door.