Review on 🔍 GXG-1987 AS8700A Handheld Carbon Monoxide Meter: High Accuracy 0-1000PPM CO Gas Detector with LCD Backlit Display - Yellow by Dave Willis

As others have said, some have bad and inconsistent handwriting. One can say 4D7 and the other 4.7M. Some reviewers note that the top values match the tolerance values, while the bottom values do not. They don't measure small resistances correctly, so they are expected to give erroneous readings. There is an instrument that can accurately measure low resistances. Search Wikipedia for the 4 point probe method to learn how to properly measure resistance below 100 ohms and why a simple meter doesn't work very well.