Thermometer / Water Thermometer - Records Maximum and Minimum Temperatures This is a multi-functional water thermometer that can measure both air and water temperatures. Battery operated. This is a new, unused, and unopened item, but it has been stored at home, so please understand this before purchasing. (Image 3 shows an opened version of the same product for reference.) *Instant purchase is welcome.* I am also selling other aquarium supplies as I am retiring from the hobby. If you purchase multiple items, I can offer a significant discount, so please feel free to ask.