While Ozark Trail 12 oz mug does feature double-walled vacuum insulation, it is not capable of maintaining the temperature of the beverage for a very long time. Still, it will prevent your coffee from becoming ice-cold in a matter of minutes – just don’t expect too much from its performance. This tumbler is vacuum-sealed and… Continue reading USA Ozark Trail Double-Wall, Vacuum-Sealed Tumbler Stainless Steel 20oz 590ml