YSI 550A-12 Handheld Dissolved Oxygen Meter with 50' Cable/Probe and Case, 0 to 50 mg/L, 0.01 mg/L, 0 to 500 Percent, -5 to 45 degree C, 9" Length x 4-11/16" Width

Measure temperature and dissolved oxygen simultaneously using highly accurate thermistors and YSI's proven polarographic technology for dissolved oxygen. The fastest DO response times on the market. Measurements are fast and easy with one-hand operation, an easy-to-use backlit display, automatic push-button calibration, and a weighted, quick-sinking probe. The YSI550A DO has a built-in calibration chamber, low-battery indicator, direct salinity, and altitude compensation. The instrument provides simultaneous readings of oxygen and temperature. Dissolved oxygen readings are automatically compensated for temperature. The PE membranes are also faster responding and require far less flow dependence. The replaceable electrode decreases any down time due to old or damaged electrodes. Simply unscrew the old electrode, replace it with a new one, and calibrate. No need to send it in or to replace the whole cable assembly. Cables: 50 foot lengths. Medium: fresh, sea, or polluted water. Parameter Compensation: automatic temperature compensation for dissolved oxygen, automatic salinity compensation with manual salinity input from 0-70 ppt for dissolved oxygen, altitude compensation for calibration. Power: 4 alkaline C-cells; Over 2000 hours at 25 degree C. Dissolved Oxygen (Percent): steady-state polarographic sensor, 0 to 500 percent air saturation range, 0 to 200 percent: +/-2 percent of reading or 2 percent air saturation, whichever is greater; 200 to 500 percent: +/-6 percent of reading accuracy. 0.1 percent air saturation or 1 percent; selectable resolution. Dissolved Oxygen (mg/L): Polarographic sensor, 0 to 50 mg/L range, 0 to 20 mg/L: +/-0.3 mg/L or 2 percent of reading, whichever is greater; 20 to 50 mg/L: +/-6 percent of reading accuracy, 0.01 mg/L or 0.1 mg/L; selectable resolution. Temperature: thermistor sensor, -5 to 45 degree C range, +/-0.3 degree C accuracy, 0.1 degree C resolution. Measures 9" length by 4-11/16" width.