Compatible with over 50 Oregon Scientific products, this thermo-hygro sensor transmits temperature and humidity readings back to a main display unit, available separately. Most main units come with a single sensor; incorporating an additional sensor like this model makes it possible to monitor conditions in another point of interest. Readings can be taken indoors or out, so it is easy to tell at a glance the conditions in the backyard, the greenhouse, the wine cellar, the garage, or the crawlspace. Transmissions repeat every 40 seconds, so information is always current and accurate.

Centered around an easy-to-read LCD digital screen, the sensor displays the current humidity level as well as the temperature. It also indicates which of the three channels the transmission is currently set to. The unit’s instruments are accurate within the range of -22 to 140 degrees F, and they travel up to 100 feet, barring obstruction, so finding a mounting location is easy.

To ensure accurate readings, the sensor should be mounted with the included hardware in a dry location and out of direct sunlight. Two AAA batteries, not included, are required for operation, and lithium batteries are recommended for use in sub-freezing weather conditions. Compactly built, the sensor measures a trim 2-2/5 by 3/4 by 3-2/5 inches, and Oregon Scientific backs it with a limited one-year warranty.