Abstract: A portable beverage container includes a generally cylindrical outer shell comprising one or more metallic materials, the outer shell including a rim along a top portion thereof, the rim defining an opening to a hollow interior; a generally cylindrical removable liquid containment vessel including (i) an opening to an interior liquid storage chamber at a top portion thereof, and (ii) a lip surrounding the opening, the lip adapted to rest upon the rim when the liquid containment vessel is disposed within the hollow interior of the outer shell, the liquid containment vessel consisting of microwave-safe materials; and an insulating layer disposed between the outer shell and the removable liquid containment vessel. The liquid containment vessel is adapted to be removed from the hollow interior of the outer shell, heated in a microwave oven, and returned to the hollow interior of the outer shell.

Abstract: This invention is a new and improved design is for a travel mug or thermos. It has a REMOVABLE liquid containment vessel (liner) that is both microwave safe, dishwasher safe, and can be made from traditional or soy plastics. A specially designed locking mechanism firmly secures the liner in place when the mug or thermos is in use.