The Sunbeam Sonic egg bark control device emits a pet-safe, ultrasonic sound at 3 levels that only dogs can hear— a method used by professional dog trainers deter your dogs or nieghbor dogs from annoying barking Battery-operated bark control device works with any breed of dog and has a 50-foot range; weatherproof design can stand alone, mount to a wall, or hang from a fence or tree LED indicator light shows when in use; light changes to red when battery needs to be changed Remote control included. best offer