Ultrasonic Cat, Dog and Fox Repeller is a battery powered scarer that can also be run on mains electric with the use of the optional adaptor. This deterrent unit will repel, deter and stop stray, feral or neighbours cats and dogs as well as preventing wild foxes from getting into your garden or outside area. Covers 40 feet / 12 metres in front of the unit, in an arc of 180 degrees.