The hidden pet fencing system is the most reliable solution to restrict your pet within a specific area that you have defined yourself. Installation and use are very simple. All you have to do is bury the wire along the outline of the defined area and place the special collar on your pet. An absolutely safe means that will effectively discipline your pet. Features: Pulsed analog stimulus (The closer the pet approaches, the stronger the stimulus it receives). Progressive stimulus (A warning sound is heard for the first time, and if it continues to move towards the boundary, the sound escalates and it receives a stimulus). Variable field-width control. Sound and visual indication if the wire breaks. Speed detection that the pet develops. Built-in lightning protection for the transmitter. Package Contents: 1 Indoor wall-mounted transmitter (11.8 x 8.5 x 3.5 cm), 1 Receiver collar with adjustable strap (6.5 x 3.9 x 3.2 cm), 1 Battery for the collar (6 Volt 4LR44), 1 Roll of wire (300 m.), 1 Power supply 12V, 1 Test lamp, 2 Extra large stakes for dogs with thick fur, 4 Screws, 20 Training flags, User manual (English).