Kapro CROSSLIGHT 3D LASER GREEN Manuel D'utilisation page 19

7) The distance between a1 and a2, should be no more than
1mm, otherwise send the laser level to a qualified technician
for repair.
4. Checking the Accuracy of the side vertical beam.
For the second vertical beam, repeat the previous marking
procedures from steps 1-7.
x
Figure # 6
a2
2 m
x
x
a1
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