[Multiple Charging Ways] USB charger powers your devices via either a wall charger, car charger or external battery. [Indenpendent Slot] Advanced 9V Battery Charger for NiMH Batteries, ultra fit for 1/2/3/4/5 rechargeable 9v batteries, even & uneven supported. 5 Led to show the charging progress of every battery. Red- charging, green- fully charged [Safety & Reliable] Improved low self discharge makes it still maintain 75% of capacity after 3 year of non-use. Adoptig technical MCU control, fast charging but providing the constant current & constant voltage in the same time.