Ultrasonic Bark Collars

Petsafe Ultrasonic Remote Trainer PUPT-100
The PUPT-100 uses a high pitched sound to discipline the dog. It has only two buttons: Positive Tone for reward & Ultrasonic Tone for correction. This has been a popular item w/mail carriers & meter readers to repel unwanted advances from neighborhood dogs

With a range of up to 50 feet, this Bark Deterrent System will not only stop your own dog's barking but any noisy dog in your neighbor's yard. Once the unit's microphone picks up any sustained barking, it emits an ultrasonic beeping that is not heard by humans but is annoying to dogs. When they stop barking, the beeping stops and they soon learn that to stop the annoying noise, they have to stop barking.

An inexpensive alternative to Bark Control systems. With a range of up to 25 feet, this unit can be used both indoors or out to stop barking. A light comes on to indicate the unit is in the process of correcting unwanted barking.