Abstract: A container assembly for containing and delivering a medicament is described. The container assembly includes a container having a first end and a second end. The first end includes an opening, and a plunger assembly at least partially disposed in the container. The plunger assembly includes a main body and at least one resilient portion at least partially retained by a groove in the main body. The resilient portion forms a seal with the container. The plunger assembly forms a temperature resilient seal with the container such that the container assembly is operable to contain a medicament between the seal and the opening at: (a) room temperature, and (b) during freeze storage of the medicament. The plunger assembly is moveable relative to the container at room temperature.