Thanks to the positionable and rubberized clip, you can attach it basically anywhere. Each arm has a pair of LED bulbs with individual switches, for more subdued lighting it is not a problem to light up each arm and each LED separately. So you have 4 levels of brightness at your disposal, which try their best to offer the desired brightness and protect your eyes. The length of the arms is 22 cm, so the light can be directed exactly where you need it. Power is provided by three AAA batteries (not included) or a USB cable (included). You can use the USB cable to connect to a USB port on any device, such as laptops, a power bank to power a light, or connect the USB cable to a 5V/1A wall charger.