Review on FGA Insulated Tumbler 16oz: Vacuum-Sealed Thermal Coffee Travel Mug with Slide Clear Lid - Ideal for Home, Office, Ice Drinks, and Hot Beverages - Black by Robert Yates

My wife used the new FGA mug for hot coffee when the outside temperature was 50 degrees. Hot coffee lasted no more than an hour; it literally became cold coffee. I think this type of jar transfers heat mainly through the lid which is not double insulated. I bet the jar will hold the temperature better if the lid is double insulated or much thicker. When I look at all my best thermal flasks, I see a common denominator - the lids are very thick and insulate very well. Otherwise the FGA glass looks nice with a cork bottom which is very soft on hard surfaces. The lid doesn't let the drink through, but the HEAT does go through.