The refractometer series are based on the principle that the refractive indices of liquids change when the concentration change. It's portable, easy, quick and no battery required, easier and more accurate than a traditional hydrymeters, more affordable than a digital meter. It's a perfect tool for adult or young, home or professional use.It features high-quality optics with smooth focusing. Its main body is made of aluminum alloy. The internal optical lens with high refractive index make up the precision optical system.The instrument is resistant to abrasion and corrosion, can be used to measure the general corrosive liquid. (But we do not recommend measuring these liquids for a long time. The residue should be cleaned immediately after measurement. ) 3-in-1 Uses Honey Refractometer This refractometer is a portable, precision optical instrument, its a convenient tool to check quality of honey and other high sugar related liquids, such as maple syrup, and molasses. Help you know ideal time for honey harvest or maple syrup production. It's 3-in-1 scale design makes you know three indexes at one time:honey moisture/ brix/ baume. The measuring range: Water Content (Moisture) 12-27%, Brix 58-90%, Be' (Baume) 38-43. Division: 0.5% Water, 0.5% Brix, 0.25 Be'(Baume).Durable & Safe materialThis honey refractometer is constructed with non-staining, non-corrosive and non-reactive chromium material which make sure hygiene and safety for all users.Automatic Temperature CompensationThe build-in Automatic Temperature Compensation feature makes it possiable to get consistently accurate reading, you don't need to control the temperature of the liquids deliberately, just make sure it's at room-temperature ( between 0-30 degree) .Portable Compact PackageThe refractometer comes with dropper, screwdriver, user manual and cleaning cloth, all included in a hard compact case, the item dimensions is 8"x3"x2", the item weight is only 8.6 ounces. makes it very portable and easy to carry. Is it complex to use a refractometer?It's easy to use.It's actually very easy to use a refractometer. There are two brief steps to use a refractometer: calibration & measuring. Calibration: Place a few drops of calibration solution on the prism and use the screwdriver to adjust the calibration screw untill the reading is proper. (The user manual record the details about the proper calibration solution and reading index.) Measuring:Place a few drops of solutions you want to test on the prism and look into the eye piece, you will get the reading.