Brand New in box - $160 New The transmitter has two modes: fence and dog training. Press the corresponding function key to switch the working mode automatically. Fence function: the fence mode is centered on the transmitter, and there are 10 levels to choose. When the dog goes out of the signal range from transmitter, the receiver will send a warning to remind the dog to return to the safe area. Warning method: first vibrate for 4 seconds, then electrostatic shock for 3 seconds, after working twice in a cycle , the receiver reminds with a warning sound until the dog returns to the set signal range. Dog training mode: Three are three dog training functions: electric shock, vibration and sound. Press the dog training function key, the signal indicator will flash, and the receiver will start to work at the same time. Release the dog training function key, and the receiver will stop dog training immediately. The intensity of electrostatic shock can be adjusted by rotating the black knob. The intensity of electrostatic shock changes from small to large by clockwise; Counterclockwise, the intensity of electrostatic shock changes from large to small. A transmitter can be added to the side or back of the house to give the dog a wider space for movement. A transmitter can be used with more than one receiver at the same time, or can be used with more than one receiver replacement.