My wife was complaining about the oven being too cold, and not working properly. I watched her a few times and concluded it was her, not the over that was the problem. She just was not setting it up properly. She wanted to call a technician on an out of warranty oven, and I knew that would be big bucks. So what would a service man do, first of all he would just measure the temperature to see if it was working correctly. So for the few dollars it cost to get this thermometer and check it myself, I did it. Turned out the oven was pretty close to this thermometer, like within 10 degrees which at 350F is no big deal. We don't expect laboratory accuracy from household appliances. But it did prove the over was functioning properly and the temperature settings could be trusted. So the wife has calmed down, taken my advice on set up, and all is well.