Work principle: ?1.This product adopts double channel enhanced, double dog training, excitation drive dogs, lightening function in one of the super ultrasonic drive dog unit, the appearance design is exquisite, easy to carry, especially suitable for outdoor work, outdoor travel and security night patrol, and all kinds of dog training use. ?2.It send out powerful ultrasonic and infrared laser role can effectively drive 20 meters outside of the dog, the woff. Use pet trainer to: ?Eliminate excessive barking  ?Eliminate jumping on people  ?Stay off the furniture  ?Stop clawing, scratching and biting  ?Excellent aid to discourage stray or unleashed dogs from approaching you or your pet It can be used a torch  How To Use Pet Trainer: ?1.Lightening: Slide the function switch to the Light, press ON button on the top. ?2. Training Dogs: Slide the function switch to the ?site, press the ON button. ?3. Chasing Dog: Slide the function switch to the ?site, press the ON button. Specifications: ?Material: ABS  ?Color: Black  ?Frequency:35-45HKZ  ?Size: 1.3x0.7x5.2in  ?Power: Uses one 9V Alkaline battery(included)  Package Included: 1x ultrasonic dog repeller 1x 9V battery 1x user manual