Abstract: A tapered body having a hollow conical interior is provided with a central recess and an annular groove spaced outside the recess. The body has a number of jet ports opening on the tapered outer peripheral surface between the central recess and the annular groove. A first set of slots extending respectively between the jet ports and the central recess is provided as is a second set of grooves extending between said jet ports and said annular groove. A tapered flow divider is adapted to fit within said body to define therewith a mixing chamber. The flow divider has means for supplying fuel and a gaseous media to the mixing chamber and holes for feeding the mixture of fuel and gaseous media to the jet ports via the central recess and the annular groove and the first and second grooves.