ZD Instrument Ltd.(Taizhou Zhengda Scientific Education Instrument&Equipment Factory) is a specialized manufacturer of electro-chemistry and soil testing instruments. Our main products are pH Meters, Soil pH & Moisture Tester, Soil EC Tester, Soil Available N-P-K Tester, Conductivity Meters, "Nutra Wand®" Hydroponics Nutrient Tester, TDS, PPM, PPt, mS/cm, uS/cm Meters, EC, CF Check, Household and Seawater Salinity Tester, Continuous Reading pH/Conductivity/ mV/Temperature Monitors and p...View More