Hi Bill and Eric,

We have another transducer in a normal thruhull in the location you mentioned as well which I suspect may be a depth unit,

I'm wondering if the one shown in the photo is a depth transducer mounted in contact with the hull rather than through the hull, (don't want to unscrew anything whilst in water)

I guess I'll have to wait until our next haul out or until the water temperature is well above its current 11 degrees to jump in a see from underneath