Specifications: 1.focus adjustable, with self-supplied illuminant for lighting the observation field. Will not be influenced by environment lighting for using. 2.with scale for reading the practical size of tiny items. 3.when it is clear during focusing with this microscope, one division in the microscope in the scale equals to 0.05mm; 0-1 equals 1mm and the measuring is from 0-4mm. 4.can magnify 40 fold for clear and precise checking and measuring. The minimum division is 0.05mm