I will be getting a cat soon and need to fit a cat flap. My back door already has a hole cut into it, which has been covered by a piece of plywood. I presume the previous owners had a cat at some point!
So, it should be easy enough to fit a cat flap but I am confused about which size/type to get as the hole is circular. It's 22cm in diameter and the door is 2.5cm thick.
I just need something that's bigger than the hole, right? Like this?