Sound pressure level measured at 0.5 meter 120 db. Power consumption: 15W. Coverage: 25 ft. radius (1,250 sq. ft.). 50 ft. power extension cord included. Ideal for use in multiple dog homes, for persistent barking problems, to train puppies not to bark, to keep your dog or the neighbor's dog quiet. Bark Free features LED status indicators for ultrasonic and for activation sensitivity. Bark free offers two tone settings: ultrasonic (only dogs can hear it) and audible (humans can hear it too) frequency settings. Audible test button. Wall-mount bracket for indoor and outdoor use. Bark free provides water resistant vinyl cover for additional outdoor protection. Bark Free has a specially designed sound selector that lets you choose ultrasonic frequencies which can only be heard by dogs and cats, or lower sound tones audible to human ears. Bark Free uses an old age principle of "Negative Reforcement using Sound" to help train dogs to stop annoyance barking. Tired of Rover barking all the time? Or how about the neighbor's dog keeping you up at night? You need Bark Free, the latest product designed to control dogs' nuisance barking.