Audio-Technica ATW-CHG2 Two-Bay Recharging Station (2000 Series) New to the 2000 Series, This two-bay recharging Station provides power to recharge NiMH batteries in two atw-t220a handheld transmitters and/or atw-t210a unpack transmitters in any combination. Maintenance charging prevents battery self-discharge until the transmitter is removed from charger. The charger draws power from a standard wall outlet. Features: NiMH batteries are charged within the transmitters versatile unit charges atw-t220a handheld transmitters and/or atw-t210a unpack transmitters (in any combination) built-in safety feature monitors cell voltage and automatically turns off the unit If problems are detected automatic shut-off if alkaline (non-rechargeable) batteries are installed automatic shut-off if damaged batteries are installed maintenance charging prevents battery self-discharge until the transmitter is removed from charger specifications: compatibility: atw-t220a handheld transmitter, atw-t210a unpack transmitter