We are the original cat door window insert company and we're thrilled to make our product, at an affordable price for you. Our cat door window inserts are custom made with solid PVC plastic or plexiglass and a locking flap. We use brushing around the flap and weather stripping around the base to keep out weather and bugs. We offer Microchip doors and customize our base to fit almost any window. Family owned & operated in the U.S.A. We donate to animal rescues for every door sold.