FeatureUsing the latest ultrasonic technology, the DAZER produces a discomforting but not harmful high frequency sound audible to dogs but not to humans. Help stop the approach of unfriendly, aggressive dogs as far away as twenty feet. Great for joggers, walkers, meter readers, bicyclists, police, home inspectors, and fire or rescue teams. It can also be used for cats at distances up to forty feet. Made of lightweight high impact plastic that includes a belt clip, low battery indicator and the 9V energizer battery.