They have a "Duckymeter", it's a baby bath floating ducky toy that has a thermometer built in so that you can be sure the temperature of the water is spot on!
It instantly activates in water and is completely submersible.
With a LCD screen it's easy to read, and updates every second, so as the water cools off you'll know when it's gotten a little "brrrr".
It is much fun for your child, and much more importantly accurate for you! Perfect combination!
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