Lentek Koolatron Dog-Off This lightweight, compact and ergonomically designed handheld unit can be used indoors or outdoors and can be heard by dogs up to 20 ft away. Dog Off can be used as a training device. Use the high pitch signal to train a dog and correct its' beh Personal Safety Alarm Button emits a 120db audible siren Handy built-in Flashlight for evening use Dog Off button for Ultrasonic Corrective Training inaudible to humans . Ergonomic, attractive and sporty design clips on belt or fits in hand comfortably. Requires one 9 volt battery (not included)