Garmin Pro 550 Plus Handheld Device | Dog Training and Tracker | Up to 9 Mile RangeExpand your training for up to 3 dogs, using up to 18 levels of continuous and momentary stimulation, tone and vibration for effective training across the board. Operation is simple, with the stimulation level vibrate selection dial at the top of the transmitter for easy access. Use the switch to quickly select a dog for on the spot training and to see where it is in the field. When your dogs are on the move, you can quickly glance at the built in