The Cyrix battery combiner is a heavy-duty relay controlled by a microprocessor that automatically connects the batteries in parallel when one of them has reached a preset voltage (indicating that the battery is charging), and disconnects them when the voltage drops below the flow level (proving that one or more batteries discharged). Cyrix battery combination unit is a very good replacement for diode insulators. The main function is that there is practically no voltage loss so that the output voltage of dynamos or battery chargers does not need to be increased.