an apparatus for manufacturing products from material which is thermoplastically deformable , as from plastic , comprising : — a mold with at least one mold cavity ; — in the or each mold cavity at least one slide ; — movement means for moving each slide ; — closing means for opening and closing the mold ; — feed means for introducing , with the mold cavity closed , said material in at least substantially plastic condition into the or each mold cavity ; wherein the movement means for moving the slide are arranged for moving said slide forward at a relatively high speed relative to the movement speed of the mold parts upon opening and closing thereof , from a position at least partly retracted from the mold cavity , such that said material , as a result , is displaced in the mold cavity for obtaining the filling thereof , preferably at a speed high such that adiabatic heat development occurs in the or each mold cavity .