Battery Brain T4 – 12v (24v) has an auto disconnect at 11.8V (23.7V). Unit has the same capabilities as the T3, but instead of a remote control there is a manual wired switch that can be mounted in a remote location. The switch is used to connect and disconnect the battery every time the push button is pressed. Suits multi driver vehicles for example Emergency Service Vehicles, Courier and Transport services, Taxi’s etc. This avoids misplaced or damaged remotes.