Measures dissolved oxygen to determine water quality in environmental testing, labs, industrial and municipal waste water, aquariums and fish hatcheries. Automatic temperature compensation as well as compensation for salinity and altitude (all factors directly effecting D.O. readings). Simultaneously displays dissolved oxygen (in ppm or mg/L), temperature readings (in C or F) and the date. Review 99 data points with time stamps, min/max and average readings directly on the large backlit LCD. Recalls the slope and date of the last calibration. Features simple one button calibration to air and adjustable membrane temperature coefficient. The electrolyte level is visible through the transparent galvanic probe with built in temperature sensor and 4 meter cord. Comes in a hard carrying case complete with built in RS-232 port, probe, spare membranes, electrolyte with syringe and 4 AAA batteries. Weight: 14 oz (397 g). Dim: 6¾ x 2¾ x 1¼” (170 x 70 x 33 mm).