Model T75 Waterproof TDS tester with automatic temperature compensation and 1 point manual calibration range: 0.0 to 1999 ppm (mg/L), replaceable MA73075 probe.
Model T76 Waterproof TDS tester with automatic temperature compensation and 1 point manual calibration range: 0.0 to 9990 ppm (mg/L), replaceable MA73076 probe.