I purchased this to be able to read at night, once my wife has gone to sleep. I almost bought one with a standard usb connection, which is like 8 year old technology, so I bought this one that is a micro usb, which is similar to my other devices.
The clip is large enough to clip onto just about any book (I just clip it near the spine to the front or back cover when I am reading a hardback book). The lights can be positioned wherever you need them. The switch on the back of each light allows for off, low, medium, and high, which is great. The entire unit is lightweight, and will provide the perfect solution for my late night reading needs.