This light but sturdy lamp is equipped with an inbuilt rechargeable 3.7V 2200mAH Ternary polymer lithium battery and features four-speed switch adjustment: brightness at 100%, 50%, 10%, and 0. It lasts 2.5, 5, or 25 hours depending on the brightness setting and recharges fully by USB cable in just 3.5 hours. This is the perfect stylish lighting solution for camping trips, picnics or excursions.