This works really well, and solves an important glitch created by unreliable space heater thermometers. My space heater has a 4 degree differential between on and off. I needed a two degree differential. The thermometer on the Lux indicates 1 degree warmer than actual temperature,(you need to have an extremely accurate thermometer nearby) so I had to add 1 degree to my set temperature. I really need to give this product a 4 1/2 star rating, so I rounded up, because of the quality and utility it offers.