Review on 🔬 Highly Accurate Veterinary Refractometer 1,000-1,050 Refractive Index 1.333-1.360 (RI) by Curtis Donjuan

I am a doctor and used to run my laboratory. I bought this as I have patients who need a urine specific gravity test. I bought this myself to see how difficult or easy it was to use and to see if it correlated with the patient's hydration status and kidney function. The one-page instruction manual shows that the calibration is correct when the connection between the blue and white squares is at 0 and 1 on two different scales. In other words, the "0" scale is the same as 1.000 of the second scale. That's great, but two scales doesn't show that it's possible to get 0 for one scale and 1,000 for the other scale. The diagrams shown in the "Instructions for Use” state that the scale is for reference only. Please refer to your product for specific scales. Don't show or tell me if I'm calibrating to 1000 or 0. It's just a piece of paper - how much effort or dollars would it cost to send an instruction manual for a product a customer bought?! It's just stupid. So send a nice case with what appears to be an accurate instrument, but give the buyer an ambiguous instruction manual. Please fix this and I will change my rating to 5 stars. If not, I have to return this product. I cannot support such laziness.