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It may seem difficult to put up a cat flap however, with the proper guidelines, it's not all that difficult. Determine how high you would like your cat flap to be (normally it's located at belly height). Mark this point on your door, and use the template provided to guide you when drilling. If you have a young kitten you can prop the door open a bit and gradually encourage it to enter. Reward it each time it goes through. Measure the Door A cat flap allows your pet to enter and exit your home at the time that is convenient