Abstract: A multiple channel tube and method of making such a tube. The preferred method includes providing a plurality of wall elements that are elongated in a longitudinal direction and that that have an elongated cross-section transversely to the longitudinal direction. The wall elements have opposite lateral sides disposed on opposite ends of an elongate axis of the cross-section. The wall elements are placed between first and second sheet members, and the opposite lateral sides of the wall elements are adhered to the sheet members to provide a plurality of channels defined between the adhered wall elements and the sheet members.