Sokkia B20 Operator's Manual page 49

3) Take the micrometer reading in the micrometer eyepiece.
One division corresponds to 0.1 mm.
4) Adding the micrometer reading to the staff graduations
reading gives the measurement value.
Example:
Staff graduation
Micrometer
※
For accurate measurement, the last adjustment of the
micrometer knob should be in the clockwise direction.
Fig.7.4
- 19 -
152 cm
+ 8.7 mm
152.87 cm