Charger has 12 slots. Charges 1-10 pcs. of AA, AAA and 2 pcs. of 9v rechargeable Ni-Cd/Ni-Mh batteries. Charges both Ni-Cd and Ni-Mh batteries at the same time. Automatically detects Ni-Cd and Ni-Mh batteries. LED light turns red in each slot when charging battery. LED light changes to green after charge is completed & automatically switches over to trickle charge mode. LED blinks when charging bad quality batteries. Charge current of 50mA+ -10 for 9V in each slot. Computer controlled with Negative delta V (-V) cut off detection. Cells do not get hot during charging process, utilizing latest Hitech Charging mechanism. Batteries sold separately.