content: I was given this as a christmas gift, and it's more than lived up to my expectations.It won't heat a cold cup of coffee, but it will keep a cup at a very nice temperature for a very long time.Works best if you actually drink the coffee, the less coffee in the cup, the more effective it is... A full cup of coffee left for a couple hours will moderately warm, but if you actually drink the coffee slowly over time, the end will still be a good temp.