If your pet is not microchipped, the SureFlap RFID Collar Tag is available as an alternative*. SureFlap collar tags contain a code that is unique to your pet so that if other pets in the neighbourhood have a SureFlap collar tag, or any other type of collar tag used in selective pet doors, they will not be able to gain access. *The collar tag is not compatible with SureFlap Microchip Cat Flaps with a serial number of 1152201 or lower.