LaMotte 1761M Dissolved Oxygen Tracer Membrane Kit. Includes 6 screw-on membranes and solution

" Measure Oxygen Concentration and Percent Saturation -Stores up to 25 Data Sets -Self Calibration This accurate instrument features a large memory to hold up to 25 data sets with both dissolved oxygen (DO)and temperature readings. Oxygen level is displayed as percent saturation from 0–200% or concentration from 0–20.00ppm (mg/L). Adjustable altitude compensation is 0–20,000' in 1,000' increments, and adjustable salinity compensation is from 0–50ppt. It self-calibrates when turned on, includes auto-power off and a low battery indicator. Includes DO electrode, protective sensor cap, spare membrane cap, electrolyte, four 1.5V SR44W batteries, and a 48" neckstrap. DO range: 0–200% or 0–20.00ppm (mg/L), resolution: 0.1%, accuracy: ±2% (0.4ppm). Temperature range: 0–50°C (32–122°F), resolution: 0.1°C/°F, accuracy: ±1°C (1.8°F). Size: 7" x 12/5" x 13/5".DO Range: 0 - 200% -0 - 20.00ppm. Resolution: 0.1%. Accuracy: ±2% -±0.4ppm. Temperature Range: 0 - 50°C -32 - 122°F. Resolution: 0.1°C/°F. Accuracy: ±1°C/1.8°F."