How do I install a PetSafe Microchip Cat Flap in a metal door?

Install a Metal or Metal Core Door requires an Installation Adaptor (sold separately). First, attach the Cutting Template correctly to the exterior of your door. Drill four corner holes as marked and cut along the indicated line using a jig saw. After cleaning the area and sliding one adapter plate over the tunnel, from the interior insert the flap with adapter into the opening and follow steps similar for wall installation.