If your dog has more "bark" than a tree, our No-Bark trainers are a safe and effective tool to help eliminate any excessive or unnecessary barking from your dog. No-Bark trainer with 9 levels of intensity for medium to extra large dogs. Uses 9V battery. Lightweight waterproof collar unit Adjustable levels of intensity Specially designed vibration sensor picks up vocal cord vibrations so it won't be activated by other dogs' barking Adjustable for low level Gentle Touch Stimulation 1/2 second corrective stimulation