• Accurate, low maintenance optical DO probe
• Intuitive, easy-to-read display

The ST400D is a practical, affordable, low-maintenance portable dissolved oxygen (DO) meter equipped with optical DO technology. This technology provides accurate results without warm-up time or sample stirring, and is not affected by interference from hydrogen sulfide. Maintain the DO probe by simply changing the sensor cap every 12 to 18 months. Meters are IP54 rated splashproof and dustproof, and feature a built-in stand for use in the lab or in the field.

The backlit color LCD screen displays DO measurement in % and mg/L, along with temperature, barometric pressure and time/date. Icons indicate electrode and battery status. To ensure accurate results, meters feature temperature and barometric pressure measurement, automatic compensation, and manual input salinity compensation. They store up to 99 data sets and the most recent calibration data for later recall.

Meter includes: electrode clip, four AAA batteries, IP54 seal components, wrist strap and instructions. 1-year warranty.

• Dissolved oxygen (mg/L)
  Range: 0.00 to 20.00 mg/L
  Resolution: 0.01 mg/L
  Accuracy: ±0.2 mg/L (<8 mg/L); ±0.3 mg/L (8 to 20 mg/L)
• Dissolved oxygen (% saturation)
  Range: 0.0 to 200.0%
  Resolution: 0.10%
  Accuracy: ±1% of reading
• Temperature
  Range: 0 to 50°C
  Resolution: 0.1°C
  Accuracy: ±0.3°C
• Barometric pressure
  Range: 50.0 to 115.0 kPa
  Resolution: 0.1 kPa
  Accuracy: ±1.5 kPa
• Salinity: manual
• Memory function: 99 data sets
• Power: four AAA batteries