Model SM13S is a deluxe rigid frame sheet magnifier that measures 95 x 30mm. Its 2.5x power acrylic Fresnel lens is sturdy and shatterproof. The SM13S is perfect for reading large areas of small print such as maps, newspapers, directories, recipes and more. It also acts as a ruler, with its easy to read markings on the side. Its flat design allows it to fit into any book, making it the perfect multipurpose bookmark.