Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Not accurate

My level was not accurate; measurements are noticeably skewed to one side. These types of levels are self-calibrating, in the sense that if you rotate them 180 degrees, they should remain consistent. I'm not sure if it is the bottom surface of the device that is not perfectly level, or if it is the bottom of the clear plastic top that isn't. Either way, it's not a good thing.