Check the listing for details. Digital Seawater Refractometer MA887 - Milwaukee. Condition: New. Listed at 114.00 USD. This refractometer does not come with a case or battery. The new Milwaukee MA887 Seawater Digital Refractometer encompasses 3 different types of user selected scales for the measurement of seawater providing for a much more precise evaluation. Each scale is temperature compensated. PSU - The newest type scale standard - Letters stand for Practical Salinity Units and is fast become the universal standard for seawater measurement PPT - The old standard of Parts Per Thousand of saturated salt. This is the oldest of the 3 seawater measurements scales S.G. - The current standard of Specific Gravity hydrometers and refractometers. The Milwaukee Instruments MA887 digital refractometer is easy to calibrate and easy to read and provides highest accuracy possible for the measurement of seawater 3 specific scales. This is the type of accuracy demanded by today's professionals and Milwaukee Instruments delivers. Specifications Range PSU PPT S.G. Temp 0 - 50 0 - 150 1.000 - 1.114 0 - 80°C / 32 - 176°F Resolution PSU PPT S.G. Temp 1 1 0.001 0.1°C / 0.1°F Accuracy PSU PPT S.G. Temp ± 2 ± 2 ± 0.002 ± 0.3°C / ± 0.5°F Calibration Automatic Listing and template services provided by inkFrog