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. Key Features:•Vibration option, perfect for hearing impaired pets •Higher intensity stimulationn levels for stubborn or hard-to-train pets Features:•For dogs 3.6 kg and up •Fits neck sizes 15 - 40 cm •4 adjustable levels of static stimulation•Covers up to 13 ares (1/3 acre/0.13 hectares) with included boundary wire •Expandable up to 1,000 ares/25 acres/10 hectares (additional wire and flags required) •Add an unlimited number of pets with additional in-ground Add-A-Dog® Receiver Collars •Run Through Prevention- Static Stimulation increases if your dog tries to run through the boundary zone •Waterproof Receiver Collar •Uses 1 x 9 Volt battery (included). System Includes; •Transmitter with Power Adaptor •Receiver Collar with 9-Volt Alkaline Battery •Surge Protector •50 Boundary Flags •152 meters of 20-gauge Boundary Wire •Wire Nuts •Gel-filled Capsules •Test Light Tool •Operating and Training Guide.