A vial including an end wall with a given perimeter, a side wall depending from the end wall about the given perimeter, and a plug wall depending from the end wall such that an outer surface of the plug wall is radially inward and spaced from the side wall. The plug wall has an attached end portion and a free end portion. The outer surface along the attached end portion of the plug wall is angled relative to the end wall by a first angle and the outer surface along the free end portion is angled relative to the outer surface along the attached end portion and extends at a second angle relative to the end wall with the second angle being larger than the first angle.