Ultrasonic Dog Repeller
Protect yourself from dangerous dogs while cycling, walking, or jogging with the Ultrasonic Dog Repeller. It produces a high frequency sound that the human ear can not detect, yet it is able to deter vicious dogs without harming them. It's even safe enough to use for training dogs! It is small enough to fit in your pocket and includes a low battery indicator. Covered under a 90 day warranty. Requires one 9 volt battery (not included).