The PetSafe Indoor Bark Control Unit is a stationary ultrasonic deterrent which emits a high-pitched ultrasonic tone to deter nuisance barking.
An internal microphone will pick up the sound of your dog's bark within a range of 8 metres and will immediately emit the high-pitched ultrasonic tone in an arc in front of the deterrent unit. The dog should associate the ultrasonic tone with their barking and to avoid hearing this high-pitched tone, the dog must stop barking.