ONLY CEDAR-GORGE CAN GUARANTEE AUTHENTICITY. BEWARE OF INFERIOR COPIES BY OTHER SELLERS ⦗MOST EFFECTIVE ANTI BARK⦘ This device high sensitive microphone isolates and detects barking up to 50 feet away, automatically emitting an ultrasonic sound wave to deter nuisance barking. Effective for all sizes and breeds of dogs. ⦗PREMIUM MODEL⦘ The only one with 2 ultrasonic high-frequency sound transmitters with 3 range levels and a test mode (verify the functionality state of the microphone and speaker). ⦗100% HARMLESS and SAFE⦘ The ultrasonic sound produced by this device is 100% harmless to your dog, other pets and completely inaudible to human ears. ⦗DURABLE and WEATHERPROOF⦘ It is made with ABS plastic material which making it durable and waterproof. The LED indicator indicates what the battery condition is.