Abstract: A portable container for liquids is provided, comprising an insulated outer casing having a narrow neck portion opening into a larger portion, and sized and configured to enclose a removable, and preferably disposable, inner vessel also having a narrow neck portion opening into a larger liquid storage portion. A releasable clamp is secured to the neck portion of the outer casing and adapted to cooperate with a substantially rigid neck for the inner vessel to securely hold the neck of the inner vessel in a fixed position with respect to the outer casing. The substantially rigid neck for the inner vessel may be formed as part of the vessel itself or may be formed as an insert for the neck portion of the inner vessel. When formed as an insert for the neck portion of the inner vessel, the clamp will seal the neck portion of the inner vessel to the substantially rigid neck to prevent leakage of the contents of the inner vessel around the neck, as well as hold the neck in position in the outer casing.