Portable nephelometric with highest precision according to DIN ISO / US EPA for water analytics, quality control and process monitoring. WTW offers robust analysis products for the measurement of pH, dissolved oxygen, conductivity, total dissolved solids and specific ions in lab, field and on-line applications serving the environmental, water and wastewater, food and beverage, educational, pharmaceutical, clinical, research and chemical/petrochemical industries. WTW has provided outstanding leadership in the design and production of superior quality water testing instrumentation world-wide for over 70 years.