This hand held Refractometer is a type of precision instrument.This model has its own light source. With the built-in light source, it is more convenient to use in dim or dark rooms and in wide field work.This Refractometer also has a built in automatic temperature compensation system.Reading: Dual scale, 0-100 ppt salinity and 1.000-1.070 specific gravityWeight: 10 oz.ZGR Refractometers have the following features:-Easy and convenient to use-Competitive price-High quality, accurate testing result-3 button cell batteries (included)-Battery life rated at more than 100 hours-White LED light source-ATC compensation range 10 degrees Celsius to 30 degrees Celsius
