5) Press the H (#1) button, to turn off the horizontal beam.
6) Use the micro – adjustment knob (#5), to turn the laser, so that
the vertical beam will merge with the plumb line below the
hanging point.
7) Mark point a2 on the wall, in the middle of the vertical beam at
the same height as a1. (see figure 8).
8) The distance between a1 and a2, should be no more than
1mm, if otherwise, send the laser level to a qualified technician
for repair.
9) Repeat the same procedure to check all other 3 vertical beams.
20
a2
a1
XX
2m
Figure # 8
Figure # 8