Simultaneously displays dissolved oxygen and temperature. Units of measure are saturation mg/L or ppm for dissolved oxygen and °C or °F for temperature. Advanced features include data hold 25 points memory auto power off automatic temperature compensation salinity and altitude compensation. Careful use and maintenance will provide years of reliable service. Easy to replace screw on membrane cap with optional extension cables. • Oxygen level displayed as Saturation or Concentration (mg/L [ppm]). • Adjustable Altitude Compensation (0 to 20,000 ft in 1,000 ft increments) • Adjustable Salinity Compensation from 0 to 50 ppt • Analogue bar graph indicates trends • Memory stores up to 25 data sets with DO and Temperature readings • Self calibration on power up • Data Hold, Auto power off, Low battery indicator • Waterproof to IP57 • Optional 1 m or 5 m extension cable • Complete with DO electrode, protective sensor cap, spare membrane cap, electrolyte and four 1.5 V batteries.