I have a Tritronics G2 Exp training collar with 2 recievers. This unit can take up to 3 dogs with the purchase of an additional reciever. The unit works well, but I have upgraded to the G3 Exp so don't need it anymore. It is about 5 years old. I have never changed the batteries. The only thing wrong with it is the battery indicator light on the charger for the transmitter does not light up, but it still charges fine. I am asking $250 obo. Located in Medicine Hat area.