Lightweight - This magnifier is lightweight, only 3.5 ounces, ergonomically designed to fit most people's hands, suitable for people who like to read for a long time.Ideal Reading Magnifier - Users can choose the appropriate viewing distance of 2-5 inches to view newspapers, cell phones, pictures, manuals, etc. Adjust to Your Comfort Lighting Mode - Adjust to your comfortable brightness level by dimmer wheel. 12 energy efficient smd leds controlled by dimmable switch, powered by 3 AAA batteries(not included). Large Viewing Area - Optical grade magnifying lens covers large viewing area without having your hands to move all the time, lens(viewing area) is measured 4.7"x 7.7" and magnifies up to 400 . Lightweight - This magnifier is lightweight, only 3.5 ounces, ergonomically designed to fit most people's hands, suitable for people who like to read for a long time.