The CM Gauge (Crack Management Gauge) is a device that sticks to an area where a crack has appeared on the surface of concrete and is able to confirm the movement of a crack in units of 0.05mm by a common measurement. Judging whether a crack in buildings or building products is safe or going to continue to change is a factor in cracks, indispensable in the selection of how to repair it, and is an extremely important element. Furthermore, this gauge would be convenient for those in the reform field such as Construction products of EXJ, J, Kartenoru joints, Alumina joints, and siding joints, would measure the movement of all parts related to shape change due to heat, and would be helpful for the measurement design of Singer joints and the quality wood choice of Singer parts. This unit comes with either 5 or 11 personal settings.