The lightwedge is an efficient book light with a streammlined design. A lighted, distortion-free acrylic lens extends across the book page, reducing shadows and glare.Since the light is emitted directly onto the page, there's no excess reflection to disturb others ***** lightwedge is thin and lightweight and easily slips into a backpack, totebag, or briefcase.Also when not in use, it is useful as a convenient bookmark stored between a book's ***** Bright LEDs that illuminate the lightwedge have two brightness levels and a lifetime ***** light can run for 40 hours on four AAA ***** lightWedg can rest on the left page and then simply be flepped over to read the right page. The LightWedge has these great features; * Thin and lightweight * Distortion-free, optical-grade acrylic lens * Sturdy, easy to handle * Also useful as a bookmark * Eye-friendly LED illumination (no bulbs to burn out) * 40 hours of light on 3-4 AAA batteries * Two brightness levels * One-year warranty for the unit *Lifetime warranty for the LEDs *Dimensions: different size for kinds of books.