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  • Measures Dissolved Oxygen and % Oxygen plus Temperature
  • Range:
    • Dissolved Oxygen: 0 to 20.0 mg/L
    • Oxygen: 0 to 100%
    • Temperature: 32 to 122°F
  • Accuracy:
    • Dissolved Oxygen: ±0.4 mg/L
    • Oxygen: ±0.7%
    • Temperature: ±1.5°F
  • Automatic Temperature Compensation via temperature probe sensor built into polarographic type oxygen probe
  • Adjustable Altitude (0 to 3900 meters) and Salinity (0 to 39%) Compensation
  • Min/Max and Data Hold functions
  • Auto Power Off with disable feature

What's in the Box

  • DO probe with membrane
  • 13ft (4m) cable
  • Two spare replacement membranes
  • Electrolyte
  • 9V battery
  • Soft case

The Extech DO210 dissolved oxygen meter is a compact, handheld instrument designed to take quick, accurate measurements of dissolved oxygen or % oxygen plus temperature in water. It is ideal for applications in municipal wastewater/sewage treatment, environmental water testing, aquaculture/aquariums, stream purification, boilers, biochemical manufacturing, beverage manufacturing, and others.

The DO210 measures DO from 0 to 20.0mg/L, % oxygen from 0 to 100.0%, and temperature from 32 to 122°F. It includes automatic temperature compensation as well as adjustable altitude and salinity compensation. Test results are displayed on a large, dual LCD display. The meter includes Min/Max and Data Hold functions and auto power off (with disable) to save battery life, which make them perfect for field or home use. These portable meters are easy-to-use, precise, and economically priced to meet your budget.


Extech Dissolved Oxygen Probe
Replacement dissolved oxygen probe


Please consider these optional accessories.

Extech Replacement Membranes
10-pack of replacement membranes for the Extech 407510 dissolved oxygen meter
Extech DO Internal Fill Solution
Internal fill solution for the Extech 407510 dissolved oxygen meter