Built in discharging function on channel II to eliminate the memory effect. Auto switch to charging mode when discharging is complete. With dV, dT, Tmax, Timer technology to prolong the life of your battery. AA and AAA are designed to be different charging current to ensure the best charging mode. Push button that controls the charging/discharging of the cells Simultaneously charge/discharge 4 batteries (the batteries are required to be the same size) The intelligent CPU controls a smart charging mode to achieve fully charge automatically. Music will be ON after fully charging and can be switched OFF with the press of a button