This collar comes with three new units never taken out of the box. It is ready to run three of your dogs at once. You can also run your tri tronics beeper collars right from the remote. This collar has 18 levels of stimulation as well as tone and vibrate. The way this unit is set up it retails for 850.00. I am selling it for 550.00. This collar was won at a pheasants forever banquet. I have never even taken it out of its hard case. For more info you can contact me at 605-395-7799 or email me at [email protected]