Portable: robust design, compact size and light weight, convenient to hold. With a compact and lightweight housing, the device is very portable. Batteries are not necessary, so you can measure at any time. Practicability: The refractometer measure the sugar content from 0 to 90% (0 to 30 degrees), is suitable for fruits, vegetables and drinks. Measurement result directly and precisely readable on measuring scales. Easy to use: Place 2, 3 drops of the sample on the main prism, close the plate and look through the window to read the Brix value. The handheld refractometer with automatic temperature compensation: 50 F ~ 86 F (10 C ~ 30 C). Note: The instrument has been calibrated before leaving the factory, so you can use it directly Do not twist the eyepiece forcibly, adjust it back and forth, if you can't adjust it, please adjust it in the opposite direction More health: Do you always worry about taking too much sugar? Not only can it measure the sugar content of fruits and vegetables in the home garden, it can also measure the sugar content of drinks that you always drink. The principle of the refractometer: Pour water into the glass and put a straw in one part of the straw, which is immersed in water looks bent out, when you add more sugar into the water, the straw in thick sugar water is more curved aussiehen. It is the principle of the refractometer: the higher the concentration of the liquid, the higher the refractive index. Correction: Take a few drops of distilled water, place it on the detection prism, and turn the zero adjustment screw to adjust the dividing line to the 0% position of the scale. Then wipe the detection prism and perform detection. Precautions: 1. You must be careful and cautious in use, use strictly according to the instructions, and not arbitrarily loose The connecting parts of the moving instrument must not collide and violent vibration is strictly prohibited. 2. After use, it is strictly forbidden to directly put it in water for cleaning, and use a clean soft cloth Wipe, the optical surface should not be scratched or scratched. 3. The instrument should be kept in a dry and non-corrosive place. 4. Avoid the loss of spare parts. Product details: Colour:Black Material: ABS Size: 17.3*4.1cm Measuring range: Brix 0 - 30% - minimum scale: 0, 2% Accuracy: Brix 0, 2% (10 to 30 C) Temperature compensation range: 10 - 30 Conforms to: fruit, vegetables, beer, alcohol, fruit juice, honey sugar. etc.