Underground Electric Dog Fence System Waterproof 2 Shock Collars for 2 Dogs The Underground Electric Fence and Collar are easy to install and operate. The wire can be buried around the designated area while the collar will fit comfortably around your dog's neck in the same way as other dog collars. It is strongly advised that you do not test out the equipment while the dog is wearing the collar. Furthermore, allow your pet to wear the collar for several days before switching the system on, to ensure that your pet does not associate the collar with correction. Color: Black, Shock Collar strap length: 26-50cm/10-19inch, Package includes: 1 x Indoor wall-mounted transmitter;1 x Power plug;2 x Adjustable receiver collars;2 x 6 volt batteries for collars;1 x Boundary wire of 300 meters;4 x Extra metal contact points;20 x Training flags;2 x Test bulbs;4 x Screws;1 x User's manual Invisible fencing is a safe, reliable and pet-friendly way to train your loved pet dog to stay within designated areas, and away from roads, pools and other potentially hazardous zones. It is also the perfect solution to keep pets away from neighbors&rsquo; gardens and flowerbeds. Please keep the collar away from other wireless signal transimitter, which may interfere the collar function. Caution:Read the instruction manual carefully before use; The electronic collar is for dogs only; Make sure to replace the batteries when they are low to avoid irregular operation; Prior to system activation, allow your pet to wear the collar for several days to get used to it, and also to prevent negative association with the collar and the correction system; The dog should NOT wear the collar for more than 12 hours at a time DO NOT test or set up system while the collar is on the dog; Supervise your dog at all times while the correction collar is on. This is especially encouraged for the first few times; Large containment area- up to 5000 square meters (53,800 square feet), over 1.2 acres