I've bought a thermostat housing off eBay, it's got two sensors attached. I'm guessing one is a temperature sensor, what's the other one for?
Rescued attachment TH1.jpg

Isn't there a sensor for the ecu and one for the instrument panel?

both are temp sensors, and as said, one for dash and one for ECU

bottom one has M10x1 thread as used on many temp sensors (if i remember right)

the photo is upside down when compared to insitue position, but from photo position, botom one is ECU sensor, angled one is temp gauge sensor

And I can confirm the above