What refractometer do you use for your tanks?

How precise measurement does it allow you to do?

I have RHS-10ATC and it has 1 division per 1 ppt,
total 100 divisions in the range from 0 to 100ppt.

If yours is more acurate than 1ppt/0.001 SG
or has scale for smaller range than 0-100ppt
please list the manufacturer/model# - thanks!