Quickly, easily and professionally frame your Power Pet Medium Electronic Pet Door PX-1 wall installation with our pre-fabricated wall adapter tunnel. Your wall adapter tunnel eliminates the need for difficult framing of the hole you cut in your wall for the pet door passageway and gives your Power Pet door installation a high quality, professionally finished look. Made of high-strength ABS composite, this convenient Power Pet door accessory fits snugly into the back of your Power Pet door and telescopes into the door's outside frame, making your wall installation simple. Just cut the hole in your wall, mount your Power Pet door with eight wood screws, slide in your Wall Installation Tunnel, mount your outside frame with another 8 screws and you're done. Installation typically takes 2-hours or less.