What is Freezepruf??? Could you be more specific. How did you use it?

Mara:
"FreezePruf" is the name of a product that allows a plant to be 9 degrees colder (for a solid 8 hours) than its true cold hardiness without causing death. A friend tried this during
our 3 days of cold weather. His temps were around 12 degrees
his Cuphea (in pots) made it through with some minimal damage.
I guess no one has heard of this product let alone tried it.
Art