Kapro Prolaser Plus 872 Manuel D'utilisation page 17

3) Mark point a1 on the wall, in the middle of the horizontal line
at the left edge of the horizontal line (see figure 5).
4) Turn the laser level counterclockwise until the right edge of
the horizontal line reach's near a1, mark a point a2 on the wall
in the middle of the horizontal line (see figure 6).
a1
X
Figure # 5
x a1
x a2
Figure # 6
1.5m
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