| Model | 499ATrDO | Dissolved Oxygen Sensor - Trace DO |
| Transmitter compatibility | 54 | Rosemount 1056, 1066-DO, 56, and 5081-A compatible |
| Flow cell option | 70 | Includes low flow cell |
| Calibration and conformance certificates - optional level | EC | Electronic Calibration Certificate (sensor calibrated against factory instrument, with test data) |