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A cat flap that runs through the wall allows your pet to go out and in whenever they want. However, you must be careful not to place it too high in the wall. This could result in energy loss and allow burglars to enter your home. A gap in a cavity could be a problem for future owners if you intend to sell your home. Glass cat doors are a much safer choice. Easy to install A cat flap that is built into the wall allows your cat to come or go as it pleases. There are of models available and they are