FIELD: forming of honeycomb products. SUBSTANCE: extrusion extension piece has inlet and outlet faces and is provided with die and spinneret, which has grid of mutually intersecting channels with different width through height. Grid of channels is positioned adjacent to outlet face. Channels define multiplicity of core mandrels of different sections. At least three core supports of equal height are positioned between spinneret flange and die plate circumferentially of die central opening. Supports may be mounted on die plate as well as on spinneret casing. Supports may be cast integral with die plate. Spinneret casing may be made convex at the side adjacent to inlet face. Die plate may have reduced thickness at the areas adjacent to inlet face circumferentially of central opening. Such construction of extrusion extension piece allows labor consumption for making this apparatus to be reduced. EFFECT: increased efficiency by reduced labor consumption, increased strength and allowable extrusion pressure. 7 cl, 3 dwg
