Kapro Prolaser Vector 873 GREEN 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 beam (see figure 5).
4) Turn the laser level counterclockwise until the right edge of
the horizontal beam reach's near a1, mark a point a2 on the
wall in the middle of the horizontal beam (see figure 6).
a1
X
Figure # 5
x a1
x a2
Figure # 6
1.5m
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