TESTO 104-IR BT Mode D'emploi page 18

11.3 Measuring range, distance
Depending on the distance of the measuring instrument
from the measurement object, a specific measuring range is
recorded.
Measuring lens (ratio of distance : measuring range)
In italics = laser
Not in italics = measuring range
* Optimised measuring distance
12. Information on contact measurement
Observe the minimum penetration depth for immersion/
penetration probes:
10x probe diameter
Avoid using in aggressive acids or alkalis.
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