The AquaMetrix AM-ODO2 optical dissolved oxygen sensor outputs a direct analog (4-20 mA) signal that can be set for percent-saturation or concentration (mg/l or ppm) or both. It can connect to the AquaMetrix AM-2300 controller, AM-2252 controller or a PLC. The sensor membrane lasts for approximately 2 years and is inexpensive to replace. The body is corrosion resistant and designed to stand up to harsh environments such as wastewater treatment, sewage treatment, boilers, agriculture, and aquaculture.