Turbine Boss 100-A Use and Care Manual

The Turbine Boss™ needs no batteries or electricity.
That's hard to believe. How does it work?
Consider the outdoor dial thermometer. On a hot day the dial is
pointing near 90° and on a cold day the dial is pointing near 30°.
What makes the dial move?
It has a thermostatic controller that expands on hot days and contracts
on cold days. Thus, the dial is moved by temperature. And like the dial
thermometer, The Turbine Boss™ gives you many, many years of
trouble-free service.