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A cat flap that is built into the wall lets your pets come in and out whenever they like. However, you must be careful not to place it too high in the wall. This can result in the loss of energy and also allow burglars to enter your home. A cavity with a hole can also be a problem for future owners if you plan to sell your home. Glass cat doors are a much safer alternative. Easy to install A wall-to-wall cat flap lets your cat to come and go whenever it wants. It's easy to put up and there are a variety of models available. Certa