Product review (4 stars): In spite shortcomings, handy to have in our RV!
We use this in a unique way.  We have a small RV, and (at the suggestion of a YouTuber) we took the probe and tucked it behind the insulation on our RV Hot Water Heater against the tank.  When the water get's to a proper temp (110 degrees F), we turn off the heate, and just use the hot water faucet for cleaning up.  Saves fuel and water, and it's nice we don't need to mix the hot and cold..

We installed the display with a piece of Velcro in a convenient place.  The down side, is this current iteration of the product only reads in Celsius. We we've posted a note next to the display with handy conversions, but we're getting pretty good at doing this in our heads.

Other posters are correct that the battery for the unit may cost more than the product itself, but we're still glad we have it!