Includes 2 electronic ID discs to control exit and entry through the flap. Up to 7 unique ID discs possible. Keeps all other animals out. LED display shows selected exit and entry lock status plus low battery indicator. Self-lining up to 50mm thick, ideal for single and double-glazing, and any panel 0-50mm thick. Wall liner available for wall insulation. Fully draught and weatherproof brush-sealed flap. Universal installation facility, can fit to glass, wood, metal or plastic. Size (H)26.5, (W)24.8cm. Door size (H)19.2, (W)16.6cm. Requires 4 x AA batteries (not included).