Decided to invest in one of these when I was having problems viewing my Kindle even in the brightest rooms. With this hooked over the top it made the screen look really bright even with the lights in the room turned off. Great for reading at night when other people don't wish to be disturbed by bright lights in the room, or for during the day to make the screen clearer. A great investment at such a cheap price for any Kindle user. It takes three AAA batteries (not included with the item) which last a really long time too.
There aren't many negatives to this. However, the only one I could see, if I had the light angling straight down onto the screen it did give a bright spot. To avoid this hold the kindle angled and point it so its facing the bottom not the screen and the aura of the light will light the screen instead. Also my father did point out that the pin that acted as a hinge for the clip was coming away from the plastic which he had to repair. Slight disappointment on a new product.