This is a 12-watt AC / DC emergency power-saving rechargeable bulb. It has 2200 mAH Li-ion rechargeable battery that takes 5 to 6 hours to charge. This bulb will light up to 2.5 hours on a full charge and has a long life of 30000 hours. This bulb is suitable for use anywhere including bedroom, kitchen, balcony, living room, warehouse, and commercial showroom.