A clock made of a metal body with a paper calendar with values ​​from 0 to 100 (1/200 mm) in increments of 10. The body of the clock is crossed by an axis that exits at the top of the clock, at the bottom of the clock the other part of the axis exits, to which a rectangular body is attached reinforced with two screws. at the end of the axis. Measuring the thickness of objects is done by inserting the measured object between the end of the axis and the head of the lower rod.