Dissolved Oxygen / Temperature DO600 Extech USA Features: Oxygen level displayed as % Saturation from 0 to 200.0% or Concentration from 0 to 20.00ppm (mg/L) Adjustable Altitude Compensation (0-20,000ft in 1,000ft increments) Adjustable Salinity Compensation from 0 to 50ppt Analog bargraph indicates trends Memory stores up to 25 data sets with DO and Temperature reading Self calibration on power up Data Hold, Auto power off, Low battery indicator Waterproof to IP57 Optional 3 ft (1m) or 16ft (5m) extension cable with probe weight. Complete with DO electrode, protective sensor cap, spare membrane cap, electrolyte, four 3V CR-2032 batteries, and 48" (1.2m) neckstrap.