Instruct: Classify Amazon reviews into positive or negative sentiment
Query: doesnt measure properly.

does not work well due to the long length, and no way for the measuring reader to tell where it is on the rod. if you want to use this to measure a brake drum, the reading is immediately wrong after expanding the claws. you could see this by zeroing the caliper, then fully expanding it and closing it. the closed reading goes from 0.00 to off by 22mm. a calibration stick is needed for large measurements, otherwise all measurements are far from accurate