Persistent pooch? Hard-headed or hard of hearing? Now you can still keep them playing safely in the garden and nowhere else. With 4 higher-intensity settings than our other collars, even dogs that are difficult to train respond well to the Stubborn Dog In-Ground Fence™ system. The safe, gentle static stimulation works so effectively that most dogs learn to stop in their tracks at the warning beep that precedes the stimmulation. The vibration option is ideal for hearing-impaired dogs, or as an alternative to static stimulation.