BRAND: Milwaukee Instruments SKU: MA887 ACCURACY: ±2 PSU | ±2 ppt | ±0.002 S.G. (20/20) | ±0.3°C / ±0.5°F TEMPERATURE COMPENSATION: Automatic Thousands of saltwater aquarium enthusiasts have dialed in the analysis with Milwaukee's salinity refractometer. No more visual readings. Get a digital readout within seconds accurate to ±2 ppt with automatic temperature compensation (ATC). DESIGN FEATURES Fast, accurate results with digital dual level LCD readout Easy measurement with just 2-3 drops of sample needed and results less than 2 seconds Automatically temperature compensated Simple one-point calibration using distilled or deionized water Easy to clean, stainless steel sample well with unit rated to IP65 as "dust tight" and protected against water jets Battery percent level indicator with automatic shut-off (batteries included) MA800 DESIGN FEATURES Specific foam cut insert to prevent meter rattle. Easy carrying handle. Strong outer plastic design. Strong fasteners for long-term use.