The invention relates to a distance measuring unit (10) for contactless distance measurement, in particular a handheld unit, with a housing (12, 40), which has a housing front side (14), which points in the measurement direction (32), and a housing rear side (16), which faces away therefrom, wherein the housing rear side (16) forms a first reference plane (AA) for the distance measurement, and with at least one measurement stop (5) of a measurement stop element (4), which can be moved out of the housing (12). The invention proposes that the measurement stop element (46) is mounted in the housing (12, 40) in such a way that it moves automatically out of the housing (12, 40) once a locking apparatus (62, 63, 65) has been released and is optionally moved at least into a first (1) or into a second (1) measurement position.