Aetertek® Dog Training Collar Vibration + Beep + Shock 550M + receiver with rechargeable remote control for 3 dogs AT-216W-3 (Various)
Very simple to use this kit of three collar corresponds to my expectations, it allows me to draw three dogs at a time with the same transmitter. The three collars have a rechargeable battery and can adjust the power with a simple dial knob position 3