Abstract: In an injection moulding machine for the production of undercut mouldings, such as plastics bumpers or fenders for automobiles, the injection mould comprises two relatively movable mould halves (1, 2) and a plurality of mould followers (4, 5, 6, 15, 16, 17) for defining the mould cavity when the mould is closed. The mould followers are all mounted on one mould half (1) and are displaceable relative thereto in directions transverse to the direction (3) in which the mould halves move relative to each other to release the moulding when the mould is opened. The other mould half (2) has recesses (28) for engaging and locating the external surfaces of the mould followers when the mould is closed for a moulding operation.