With 3 coloured scales: density, sugar content and potential alcohol degree. Other units however have a connection with the density or specific gravity. The specific gravity of pure water is 1 g/cm³.
XINJIAYI Refractometer Beer Brix Refractometer Meter with Two Scales Specific
Wine & Beer Hydrometer with Plastic Trial Jar
Home Brew Hydrometer with 100ml Trial Jar- Wine & Beer Making Equipment - IN-032
HS Triple Scale Hydrometer with Plastic Trial Jar for Beer Wine Making Home Brew
Stevenson Hydrometer with alcohol scale for Homebrew Wine & Beer
Hydrometer with Alcohol Scale & Plastic Jar Tube Alcoholometer
