We zd instrument factory, is a specialized manufacturer of electro-chemistry instruments. Our main products are ph meters and waterproof pen ph tester; nutra-wand t. D. S meters, ec check, cf check, ppm tests, ppt tests, us/cm tests, ms/cm tests, ph combined, ph skin, oxygen(do), conductivity&orp electrodes and accessories. Bearing in our minds that our customers need most reliable measurements, we have always been doing our utmost to supply quality products in our yeas of history. Most of our products are CE certified, and are sold to all the continents in the world. At the same time, we deal some other lab instruments, such as refractometers, lab glassware and etc. In order to meet our customers' request. With our quality products, efficient service and competitive price, we sincerely hope to have more and more users.