Especially designed for the partially-sighted, it gathers' light so that the image appears exceptionally bright , and the optical quality is excellent, crystal clear.
Other features: tall design (they call it the 'hedgehog') with easy-grip sides, and ingenious shape that 'locks in' to the crease of books so that you can read each line to the very edge; a green 'guide line' stops the eye wandering; a hard plastic carrying case to protect it.
If you have very severe eyesight problems and want to read books and magazines (as opposed to occasionally reading small print or labels in the supermarket) then I would recommend either this one or the previous item (with the light). As with all magnifiers this powerful, you will only see a few words at a time (there's no choice, it's simply the way optics work), but for sharpness and brightness this (and the version with the light) are by far the best for prolonged reading.