https://notes.io/w3efm
https://yamcode.com/how-to-install-a-cat-flap-28
It is possible to install a cat flap into an upvc panel or double glazing sealed unit. However, the most effective solution is to put in a new glass pane with an already-made hole. Take note of the instructions that will be provided with the kit for cat flaps, and follow them carefully. Ensure that the shape drawn (be it square or circle) is accurately drawn on the template. Safety If you have a dog or cat and want to let them in the garden without opening the door, a microchip activated pet flap in your door