Suitable for aquaculture, water source monitoring, sewage treatment and environmental protection monitoring, especially for outdoor purposes. Main Features ?Large LCD screen with controllable white backlight. ?Humanized designs like rack and skid proof shell make it more convenient for users. ?DO mode has functions of ATC, auto salinity compensation and auto pressure compensation. ?New structure polarographic DO electrode can measure temperature, salinity and dissolved oxygen simultaneously, equipped with special DO electrode calibration sleeve, only need 3~5 minutes for polarization. ?Built-in microprocessor chip with functions of auto calibration, auto temperature compensation, data storage, function setup, self-diagnosis, auto power off, low voltage display. ?Combined diaphragm cap makes it extremely convenient to replace the sensitive membrane just by screwing the new cap to the electrode. ?Grade IP57 waterproof housing and equipped with optional carrying case.