Has anyone tried this product? Drawback is it has to be returned to the surface to get the temperature reading. Says to keep at depth for 30 seconds minimum. I suspect that the water that enters the tube helps to buffer changes of the temperature indication as it is returned to surface.

[Linked Image from cdn11.bigcommerce.com]

It isn't what we don't know that gives us trouble, it's what we know that ain't so - Will Rogers