USB Rechargeable Easily charged with built-in USB; directly plug into laptop, power bank, adapter, car charger, or USB outlet for recharging; no additional cables needed. Built-in 200mAh lithium battery; 1.5 hours charging provides up to 8 hours of runtime at selected brightness setting. 2 Brightness Levels 50% and 100% brightness available. LED reading light adjusts between two levels with a simple press of the button. Short press to switch brightness; long press to turn off. Features brightness memory function to retain previously selected level. Flexible Reading Light Can stand alone or clip securely onto books. LED lens rotates 90 degrees counter-clockwise, 90 degrees clockwise, and 45 degrees downward. 315-degree flexible neck allows precise positioning to direct light exactly where needed. Lightweight & Portable Compact and lightweight design at 1.38 ounces. Ideal for travel and nighttime reading. Folds flat and stores easily. Perfect for use on airplanes, trains, or in cars. Great as a gift.