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It is possible to install the cat flap inside a door panel made of upvc, or a double glazing glass sealed units, although the best option is to have a new glass pane with a premade hole installed. Take note of the instructions that will be included in your cat flap kit, and follow them closely. Ensure that the shape drawn (be it square or circle) is accurately represented 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