I have purchased several different brands of contour gauges like this one, many (including this one) claiming to offer the best accuracy with teeth as small as 0.050 inch (20 teeth per inch). My guess is that sellers misstate this and believe (correctly, in most cases) that caliper gauges aren't actually used to check thickness. Teeth one of the ones I measured: 0.055 inch / 1.4 mm (about 18 teeth per inch). Most others that claimed "0.050" tooth thicknesses were at least 1/16" (0.063") thick. Another disadvantage of this device is that the teeth are much shorter than most competing calibers. The maximum depth it can measure is no more than 1.22 inches (31mm). I'd give it 3.5 stars if I could, but 4 stars seems a bit generous considering this sensor doesn't live up to advertised specs. But other than that, it's probably a good measure.
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