iMake 3 Scale Hydrometer.
The iMake 3 Scale Hydrometer allows you to keep track of your home brew fermentation’s progress. You can determine the finished product’s alcohol content by taking readings before and after fermentation. You then compare the two readings.
This 3 scale hydrometer also allows you to verify when your batch is ready to bottle, by showing you your brew's specific gravity.
Simply suspend the Hydrometer in a sample of your wort to get the reading. The hydrometer's plastic outer packaging doubles as a trial jar.
Full instructions are included, or you can find them here.