This Product Is Mainly Used to Prevent Being Attacked by Dogs When Going out. The Product Uses 9V Salty Battery. The Ultrasonic Energy Is about 125db/30cm, and 2800mcd Strong White Light, Which Can Produce Strong Effects on Dogs and Cats (Human Ears Cannot Hear) it Will Cause Uncomfortable and Unbearable Interference to Animals, and This Harsh Sound Will Make Dogs Feel Inappropriate When Animals Approach and Make Them Very Frightened and Flee in Panic. In the following Cases, the Effect of Driving Dogs Is Not Good: 1. the Dog He Keeps, Because It Knows That the Owner Will Not Hurt Him; 2. Noisy Environment, Such as Downtown Or Roadside; 3, the Dog with the Owner-the Dog Exploits the Force; the Trained Large Dog-Well-Trained; 4. When the Battery Voltage Is Too Low-the Transmitting Power Is Low. the above Situation Will Not Affect the Use Effect of This Product, Because Their Own Dogs, Dogs That Often Go Shopping, Dogs with Their Owners and Trained Dogs Will Not Bite People Randomly; Note: usually, Don't Tease the Dog with Dog Drives on Purpose, Because It Is Not Surprising That the Dog Listens Too Much. When the Light in the Dog Drive Gear Is Obviously Dim, Replace the Battery in Time,