Cleaning of excess dirt
 
 If the instrument has be subjected to contamination or excessive in its surfaces (eg. Soil, you need to follow a different method.

First, use a dry lint-free cloth to remove the excess dirt. 

Second step is to wet a lint-free cloth using a non-abrasive, solvent free neutral soap and clean only the instrument’s surfaces very gently (please do not clean the lenses with any kind of soap).

Third step is to remove any excess of the solvent free-neutral soap by whipping with a dry lint-free cloth.

Fourth step is to use a wet lint-free cloth with Isopropanol to wipe the surfaces plus the instrument’s accessories. 

Last step is to use a dry lint-free cloth to dry the instrument’s surfaces.  Again, if you need to clean excess dirt from the lenses please wet the special lens wipe with isopropanol and follow the steps mentioned before.   
So as to clean the lenses, please wipe them gently using a wet special lens tissue with Isopropanol. 
 
 
-NOTE!!!  Be careful not to scratch or damage the display while wipping Using solvents stronger than Isopropanol can damage or resolve the labels on the back of the instrument
This instruction is also available as PDF (see attachment)