The CR200-series dataloggers vary in several ways from our other data loggers. The CR200-series, initially designed to work in the field as wireless sensors, do not provide the same level of accuracy as our other data loggers. The CR206, CR211, and CR216 have built-in spread-spectrum radios; other telemetry options are limited. The CR200-series dataloggers also have a one-year warranty, compared to the three-year warranty for our other data loggers.