Review on Brix Refractometer with ATC - Dual Scale for Wine Making, Beer Brewing, and Homebrew Kit: Specific Gravity & Brix Hydrometer by Emily Quintana

So easy. Nobody really seemed to explain how it works. This is a sealed unit so no liquid/juice actually enters the instrument. There is a fold-out piece of plastic on the slanted part at the front of the device. You simply fold the piece of plastic up, exposing the sloping piece of glass underneath. You put a few drops of juice on the jar, then put the plastic lid back on the jar and squeeze the juice between the plastic and the jar. Make sure there are no bubbles between the glass and plastic and you now have a very thin sample (like a two-pane microscope). If you look through the hole in the back you will see scales. The top reading on the scale is colorless and the portion below the reading is blue. The dividing line between the blue part and the colorless part is your reading on the scale. Brix is on one side and specific gravity on the other. When you're done, flip the plastic over, wipe down the glass and plastic, then you're ready for another pattern. Grape by grape, grape by grape, you'll use it again and again!