Kapro PROLASER VECTOR 888 Manuel D'utilisation page 13

However, in field conditions a difference of up to .25" (6mm)
is acceptable.
Vertical Line Calibration Test
1. Set up the unit about 60' (20m) from a wall or any stable
vertical object.
2. Place a plumb bob style line level against the wall
hanging directly down to mark an accurate vertical line.
3. Level the unit as accurately as possible and position the
laser so that the V1-axis is pointing in the direction of the
line level on the wall.
4. Press the V1/V2 button and rotate the laser so that the
beam touches the edge of the line.
5. Check to see that the laser touches the line in all places.
6. Repeat the steps for the V2-axis.
7. If any of the beams seem to be inaccurate, repeat the test
with the line level repositioned against another area of the
wall. If the result is the same follow the instructions given
in the Warranty section of this manual.
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