Smart Flap Microchip Cat Flap has a UK power supply and one tunnel extension (additional tunnels are available for purchase). Smart Flap Microchip Cat Flap's features mean that no collar is needed so there is no chance your cat will be caught on its collar as the Smart Flap Microchip Cat Flap is operated by your cats existing microchip. Smart Flap Microchip Cat Flap helps to keep out unwanted cats and has a strong door and locking mechanism. Easily fitting common 17cm square openings or 21cm diameter holes Smart Flap Microchip Cat Flap automatically detects light levels and gives you the option to keep your cat indoors during the hours of darkness. In case of a power cut the optional PP3 backup battery ensures that the Smart Flap Microchip Cat Flap won't fail and with vet mode sick cats can be kept in until fully recovered. A magnetic latch and combined draught excluder helps Smart Flap Microchip Cat Flap keep the weather outside and an audiable beep on entry lets you know when your cats are home. Suitable for programming up to 31 cats microchips Smart Flap Microchip Cat Flap works with UK and European 15 digit microchips.