The ORP-200 is a professional-grade ORP meter ideal for all ORP testing, including anti-oxidant measurement, water purification applications, ionizers, agriculture, aquariums & aquaculture, chlorine monitoring, cooling tower disinfection, environmental testing, fruit & vegetable washing, hydroponics, metal finishing, ozone system monitoring, pharmaceutical & medical applications, pools & spas, pulp bleaching, vineyards & wineries, and water treatment.