A heatable container, comprising: a base; a cover; an elastomeric pressure release valve provided in a first valve aperture in the cover; an indicator disc provided in a second valve aperture in the cover, wherein the indicator disc includes an aperture in the indicator disc; and an indicator stem provided in the aperture in the indicator disc; wherein means is provided for permitting fluid communication to atmosphere while in a rest position, characterized in that the means for permitting fluid communication to atmosphere while in said rest position includes at least two flanges provided in the aperture in the indicator disc and the at least two flanges are on the indicator stem, wherein a channel is formed by the at least two flanges and the channel provides the fluid communication to atmosphere, wherein the pressure release valve: consists of a disc sized for the first valve aperture and has spaced peripheral flanges which overlie top and bottom faces of the cover to removably secure the pressure release valve to the cover; and includes a slit or slits, wherein the pressure release valve will deform under pressure within the container to open the slit or slits and allow steam to vent while maintaining a desired operating pressure, and wherein the indicator disc is configured to deform and be blown from the second valve aperture in the cover when a pressure in the container rises above the desired operating pressure. a base; a cover; an elastomeric pressure release valve provided in a first valve aperture in the cover; an indicator disc provided in a second valve aperture in the cover, wherein the indicator disc includes an aperture in the indicator disc; and an indicator stem provided in the aperture in the indicator disc; wherein means is provided for permitting fluid communication to atmosphere while in a rest position, characterized in that the means for permitting fluid communication to atmosphere while in said rest position includes at least two flanges provided in the aperture in the indicator disc and the at least two flanges are on the indicator stem, wherein a channel is formed by the at least two flanges and the channel provides the fluid communication to atmosphere, wherein the pressure release valve: consists of a disc sized for the first valve aperture and has spaced peripheral flanges which overlie top and bottom faces of the cover to removably secure the pressure release valve to the cover; and includes a slit or slits, wherein the pressure release valve will deform under pressure within the container to open the slit or slits and allow steam to vent while maintaining a desired operating pressure, and consists of a disc sized for the first valve aperture and has spaced peripheral flanges which overlie top and bottom faces of the cover to removably secure the pressure release valve to the cover; and includes a slit or slits, wherein the pressure release valve will deform under pressure within the container to open the slit or slits and allow steam to vent while maintaining a desired operating pressure, and wherein the indicator disc is configured to deform and be blown from the second valve aperture in the cover when a pressure in the container rises above the desired operating pressure.