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Professional cat flap installers can install your pet's door into either a door or a wall. The wall-mounted version is more secure since an intruder is unable to get through. It also helps to prevent draughts and reduces the energy costs. The Tasker will mark the location where the cat flap should be inside your door, and then cut the corners. will also sand down the edges of the frame to give it a smooth surface. Microchip cat flap