The metal is poorly cast with holes right at the tips of the calipers. In the photo he likes to read -0.03 mm. And this time the picture turned out to be 0.05 mm at the zero point, it does not slide smoothly and jams. I have to loosen the screw to get through some points. Poorly finished due to poorly cast metal. Scuffs aren't polished, too light. I've used these countless times at work, but they're too light. Maybe aluminum. Cheap and disappointing.