Cross laser supplemented with a reference vertical line. A direct plumb function using a laser cross fired at the ceiling and a laser plumb pointing at the floor. Perpendicular alignment of vertical laser lines. 2.5° self-leveling range, 2mm/10m accuracy. The device can be rotated on the base using the fine-rotation knobs to precisely direct the beams. Height-adjustable feet with removable rubber ends. RX-Ready: the receiver of the RX 51 laser beam, which can be added to the device, enables detection of the laser line up to a distance of 50 m.