EXTECH SDL 150( DISSOLVED OXYGEN METER SD LOGGER)

Dual backlit display of Oxygen Concentration and Temperature
Measures dissolved oxygen from 0 to 20.0mg/ L and 0 to 100.0% oxygen plus temperature from 32 to 122° F ( 0 to 50° C)
Automatic Temperature Compensation from 0 to 50° C via temperature probe sensor built into polarographic type oxygen probe
Offset adjustment used for zero function to make relative measurements
Stores 99 readings manually and 20M readings via 2G SD card
User programmable sampling rate
Built-in PC interface
Min/ Max and Data Hold functions, Auto power off
Complete with 6 x AA batteries, SD card, probe, two spare replacement membranes, electrolyte, and hard carrying case