The OXY 7 portable oximeter performs dissolved oxygen and temperature measurements.r- With amperometric sensorr- Auto Cal from 1 to 2 pointsr- LCD screenr- Self-diagnosis message, battery level and calibration error, with temperature compensation and on-screen indication of calibrated standardsr- Includes standards, sensor and manualr- Dimensions (mm): 86x33x196r- Weight (g): 295r- Works with 3 1.5 AA batteries