Abstract: The invention relates to the moulding of an expanded or foam plastics container (10) with a rim flange (14) projecting radially outwardly from the container side wall (12) about the mouth (13) of the container. This rim flange is similar to the roll type rim flange of a cup thermo-formed from plastics sheet material and is capable of capturing a snap-on lid. The mould tool for moulding the container (10) comprises male and femal mould parts (16, 17) which are assembled to form a mould cavity (18) defining the container (10). Heating/cooling cavities (21, 24) are provided in the mould parts adjacent the mould cavity and the heating/cooling cavity (21) in the male mould part is connectable via passageways (41, 44, 45) controlled by a valve to the mould cavity (18) adjacent the rim flange moulding zone of the mould cavity.