I hoped these calipers would be as good as IP54 digital calipers from Shahe. Unfortunately they're not. The dial mechanism was misaligned so badly that it pushed the jaws out of parallel. The needle was rubbing on the crystal. The depth gauge was ground at an angle. After fixing the alignment they became okay. Reasonably smooth and repeatable. They measure a 25mm standard as 25.02 and 50mm as 50.02. Usable, but I expected higher quality.
Best quality and accurate.