Abstract: A container which has a body portion, a neck portion and a radially outwardly extending flange intermediate and integral with the body and neck portions is blow-molded in a mold which has at least two mold elements one of which is mounted on the other for displacement in the axial direction of the mold. The mold elements have chambers which substantially conform in shape to those of the body and the neck portions of the container, the mold elements together defining an annular recess in which an intermediate portion is formed during the blow-molding operation, such portion having a pair of radially outwardly extending sections, and a connecting section extending between radially outward marginal portions of the radial sections.