(Radio Systems) Stubborn Dog In-Ground Fence keeps your strong-willed dog safe and inside your boundaries. Five progressive stimulation levels stop your stubborn dog from stepping out of the fence. Has tone plus vibration to use for training mode. Low battery light indicator. System includes transmitter with power adapter, operating and training guide, 9-volt battery, 500 feet of 20 gauge boundary wire, 50 training flags, test light tool, and one waterproof receiver collar (6.5 oz). This system is recommended for dogs 30 lbs. or over, and can be an expandable system that works for multiple dogs with the purchase of additional collars.