This is a water meter,there are many small parts that assembly together, it is very precise and have a very tight tolerance, the customer didn't have 3d file and only sent us a real sample, we reversed engineering and designed the whole 3d file according to sample, then make mold, we have very precise mold device,the tolearance reached +-0.01mm, it matched very well after assembly and have a very smooth rotation and good function for use, the customer also visited our factory and very satisfied with mass production products, he introduced us to some of his friends and partners. Thank him very much.