NIHON ICHIBAN Leaf Thermometer

These do work. I had a couple of cold nights of mid 40's and the leaves scattered throughout the house were brown. Turn on the heat and they soon turned green. I touched one and my 96.8 degree hand turned the leaf yellow. The kitchen leaf turns a yellowish green when cooking. Finding a neutral temp place for the leaves were my biggest task. I found it best to place on wood, plastic, book or cardboard surfaces. Glass or the wall is too cold for an accurate representation temp.

Worked as advertised. Too bad only a couple survived when my dog ate the package.

Lovely thing - a useful (yes, it sounds like an oxymoron) decoration. Allows you to visualize the temperature in the room in a very natural way - if hot, then the leaves turn yellow, and if it is cold, the leaves go brown or even black (as if frostbitten).