Review on Ade Advanced Optics AO 81150 14 Refractometer by Tutcht Cobb

This refractometer is inexpensive so I didn't have high expectations and wasn't surprised by its unstable performance. I use a refractometer to measure the sugar content of the maple syrup I'm making this spring. I've tried calibrating the refractometer with a store-bought sample of maple syrup, but the refractometer doesn't hold up to the calibration. I will set the refractometer at 67% when I measure the syrup from the store and after 3-4 days the same syrup shows 62% or a different number. I make sure the sample is at room temperature and wait 30 seconds after applying the syrup to the refractometer, the results just aren't always reproducible. So I just take the syrup value from the store and then adjust my homemade syrup for the day. factory bypass. So don't buy it if you don't understand its limitations, and don't take it easy if you want to keep the quality.