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It is possible to put an apron flap inside the upvc panel, or even a double glazing sealed unit. The best alternative is to install an entirely new glass pane that has a pre-made hole. Follow the directions that came with the kit. Make sure that the shape you have drawn (be it a square or circle) is accurately drawn on your template drawing. Safety A microchip activated pet panel in your door made of upvc is a great option when you have a pet or cat and want to let them out in the garden, but don't want to open the door. T