Fowler 52-660-026 LED Magnifier, 4X Magnification Folding pocket magnifier enhances the size and resolution of an object or image for a variety of applications including jewelry-making, watch-making, electronic inspection, book-reading, and various hobbies Built-in LED illumination has white and ultraviolet bulbs for illumination options Plastic lens pivots into the case for storage LED lights require two 2016-type batteries (included) A dioptric number and a magnification number are not the same thing. Diopter strength represents a specific magnification power (X). For example, a 5-diopter provides 2.5X magnification (at a distance of 8")