RD-4 Rectangular Lighted Magnifier with 2x Lens and two light levels, large led cob bulbs for excellent illumination for inspection and high contrast for low vision reading. Large 4.25" x 2.5" Inch, wide field of view lens makes this an ideal reading and inspection magnifier for books, text, graphs, maps, parts, coins and large surface inspection. Small 10x secondary 3/4" lens in handle allows for high magnification when needed. Ultra bright High Contrast "Cob" LED bulbs that are extra large long bulbs provide amazing illumination, better light means increased visibility and contrast for Low Vision issues and lowers eyestrain when reading. Also recommended for early to early mid-stage macular degeneration. Uses 3 "AAA” batteries