Kapro Prolaser Plus 870 Green Manuel D'utilisation page 17

3) Mark point a1 on the wall, in the middle of the horizontal line
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
a1
X
1.5m
x a1
x a2
Figure # 6
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