Conveniently charges 4 AA or AAA NiMH rechargeable batteries at the same time. 3-5 hour charge time with auto shut off to prevent overcharging and battery damage. Manufactured in China. The charger is equipped with audio and visual alerts. A red light means that charging has started, and you will hear an audible beep when charging begins. A yellow light appears when charging is 50 percent complete and charging is continuing. A green light means charging is complete, and the batteries are 100 percent full. You will hear an audible beep upon completion. If a bad battery is detected, a red X will illuminate, and the charger generates a repetitive audible beep upon detection. Audio and visual alerts:Red light - Charging has started; audible beep when charging begins. Yellow light - Charging is 50% complete and charging. Green light - Charge is complete and batteries are 100% full; audible beep upon completion. Bad Battery Detection Alert - If a bad battery is detected a red x will illuminate; repetitive audible beep upon detection.