Abstract: A method and apparatus for forming intimately fused, multiple layer co-extruded adhesive tapes. The apparatus includes a co-extrusion die having an outlet aperture therein of elongated width and reduced height and first, second and third interior extrusion channels which merge in the interior of the die to form a common outlet channel which passes outwardly through the outlet aperture. The apparatus is operative in accordance with the method by feeding a first pressurized stream comprising a molten elastomeric based adhesive polymer to the first extrusion channel, a second pressurized stream comprising a molten flexible thermoplastic polymer and an elastomerically compatible coupling agent to the second extrusion channel and a third pressurized stream comprising either a molten flexible thermoplastic polymer or a molten elastomeric based adhesive polymer to the third extrusion channel.