First of all, I have to say that when I initially took this reading lamp out of the packet it came in I wasn't very impressed. As its' low price might suggest it is very cheap and plastic looking. It isn't supplied with batteries, so you'll need to have three AAA batteries to use it.
However, in use it is very good. It is big enough to cover a large size paperback book and lies across the page. The LEDs are spread along the length of it and illuminate the page evenly so that reading is easy in a dark room. The on-off is via a rotating knob on the side which allows you to adjust the brightness to suit.
So far I've been using it for around a month on a set of batteries and it is still going strong.