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Make sure this fits by entering your model number. Human clinical refractometer 3-in-1 testing of Serum protein, Urine specific gravity, and Refractive index MEASURING RANGE: Serum protein: 0 ~ 12 g/100 ml ; Urine specific gravity: 1.000 ~ 1.050 ; Refractive index: 1.333 ~1.360 RI

Make sure this fits by entering your model number. Range: 0-100ppt (0-10% Salinity) and Density/ Specific Gravity 1.000-1.070 1ppt Salinity and 0.001 g/cm3 Density Resolutions Water or a salt (brine) refractometer preferred by aquarist, it checks saltwater & brine or salinity of water, best for aquariums and marine monitoring