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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).
Figure # 5
approximately 5m
Figure # 6
