Level
Automatic levels, such as these from Leica and hedue, automatically adjust the target line to the horizontal by means of a compensator. Since the compensator has only a limited working range, presetting by means of the adjusting screws and the circular bubble is necessary. The levels can be used to determine height differences or to align machines and structures.
A digital level simplifies the determination of height differences quite considerably. Levelling rods are used on which a barcode is printed. The digital level is able to record the barcode and show the height difference between two readings on the display.