Features: * For any yard up to 100 acres * Expands to any number of dogs * 9 volt receiver collar with five adjustable power levels * Warning tone plus vibrate before correction * Anti-linger mode built in to receiver collar * Factory 20 gauge solid copper boundary wire * Includes SportDog transmitter with power adapter * 100 percent waterproof receiver collar * Operating and training guide included What"s In The Box: * Radio Systems SDF-100A Sportdog In-Ground Fence System