Rebzar Laser Line Pro Spirit Level 2.5 m Tape and 1/2 ft Ruler for Multiple Purposes (Black) Combines a fine-tuned tape measure, a triple-positioned Leveling bubble, and a NEW laser level to provide maximum results. Note-   Laser Ranging Error that is given as "+/-1.5mm at 10m and 25m" If the laser is the Vertical Level or the Horizontal Level, you shouldn't adjust the Beam.