Quick-charging unit automatically recharges two Sennheiser BA 2015 batteries. The batteries are either inserted directly into the charger or remain in their bodypack transmitters/receivers of the evolution wireless G3 100, 300 and 500 Series, 2000 Series, Tourguide SK 2020-D and EK 1039. Several charging units can be daisy-chained and powered by one power supply unit.