Abstract: An apparatus for the production of molded shells and bodies of plastic material by a rotational molding procedure within an electroplate mold includes a double-walled hollow body which is heated up and cooled down by a heating and cooling medium. A box which contains plastic material can be fitted on to the mold. The mold and the box are jointly pivotable so that the plastic material can pass into the mold and fuse at the wall of the mold. At its rear wall, which is remote from the internal contour which produces the molding action, the double-walled hollow body has a multiplicity of intake and discharge openings for the heating and cooling medium so that heating and cooling can be effected specifically and quickly. The total discharge cross-section is greater than the total feed cross-section whereby the hollow body remains substantially pressure-less.