This Engine Overheat Detector is a two-wire, non-polar, normally open detector that closes when the engine's cooling water temperature reaches 200°F. It is wired to, and activates, a visual and/or auldible boat alarm device.
•Multi-voltage — works with 12, 24 or 32 volts DC
• Sender has 1/2" MPT and installs into an available 1/2" FPT plugged hole in the engine block