Abstract: A pair of interengaged slide fastener stringers of elongate length are longitudinally advanced in an intermittent manner over a clincher die and a heater plate. An end stop is vertically driven by a punch above the clincher die and is attached to the stringers at a terminal end of one of the longitudinally spaced chains of coupling elements. A portion of the stringer tapes is heated and fused adjacent to the terminal end of the coupling element chain substantially simultaneously with the end stop attaching operation. Such fusing operation is carried out by a presser vertically movable for pressing the stringer tapes against the heater plate.