Cat Mate Elite I.D. Disc Cat Flap with Timer Control - White Includes 2 Electronic ID discs (up to 8 unique ID discs possible). Keeps all other animals out. Requires 4 AA Batteries 9-12 months use. Extra discs ref.310 LCD Display shows selected entry and exit lock status, cat location and time flap last used for up to 3 cats. Timer function controls access for all of your cats e.g. to keep cats in at night. Self lining up to 2 inches, ideal for all types of installation. Frame Rain Seal & fully draft weatherproof brush sealed flap. Cut out Size 6.5"W x 7.5"H Dia 9"