This magnifier is manufactured with a high quality optical glass lens system. This provides a large flat field, freedom from distortion, brilliance of illumination, and eliminates fringe color or shading. This 1⅜" diameter 4½X power magnifier with focusing mount is easily raised and lowered. The machined base holds the Henry Disc rigidly at the proper focal distance. Henry Classification Disc available for tenprint classification. The Locking Ring is highly recommended for use with this magnifier. Weight 12 oz.