Barkbuster, developed by veterinary technicians in the USA, is a humane and effective way of helping cure your pets behavioural problems. Whenever your pet misbehaves, simply point the unit and press the button. Your pet will hear a high frequency but harmless sound pulse. Say "No" and your pet will associate the sonic pulse with bad behaviour. Also helps to repel aggressive dogs and uninvited cats. Runs on 1 x 9V battery (not supplied