Returned back to store....never leave home without unplugging it..mine started smoking on the controller thank god I was home I returned it back to kohls where I purchased them I had the wrap around the neck and shoulders and the xl flat one one started smoking and the other one kept giving me a F not sure what that meant but it wouldn't heat up anymore only had both for less than 6 months I returned no more for me User's recommendation: Unplug after done,or don't purchase I don't trust it thank God I was home when mine started smoking.