of a number of manufacturing techniques including injection molding and extrusion in one embodiment the hollow insert is a plastic material capable of producing audible and or tactile feedback when makes a physical mechanical connection that is when the hollow foam duct 10 is connected to a member in a host vehicle hollow insert 10 may be configured to provide feedback to inform users a connection is secure in one embodiment the hollow insert 30 has a compressive strength that is the same or higher than the compressive strength of foam sheets 12 and 14 which form the hollow foam body ultimately formed into hollow foam duct 10 in one embodiment the hollow insert 30 has a tensile strength that is the same or higher than the tensile strength of foam sheets 12 and 14 in one embodiment the hollow insert 30 has a hardness that is higher than that of foam sheets 12 and 14 wherein hardness refers generally to the resistance of the material to compression indentation and scratching hollow insert 30 may be placed at the end or connection point of hollow foam duct 10 hollow insert 30 may be configured to extend a predetermined distance into the hollow duct 10 from on the low end of the range about 0 25 in to about 1 5 in to on the high end of the range from about 2 in to about 4 in shorter and longer depths are contemplated depending on the nature and shape of the connection to be made referring to fig3 a removable plug 35 is shown that may be used in the manufacture hollow foam duct 10 an exemplary manufacturing procedure is generally outlined in fig4.