is symmetrical with respect to a vertical plane of symmetry which includes the central axis distal end ports or perforations are in the symmetrically arrayed walls of a triangular section of the tube which at least characterizes the region of tapering section and which conforms with the triangular shaped space between the vocal cords for added ease of insertion into the patient 39 s trachea the reducing taper of the roughly triangular shaped section extends preferably and optionally to form a wedging fit against vocal cords with or without the assistance of a conventional inflatable cuff of similar sectional profile application_number US 82722501 A description 0025 fig1 illustrates the currently preferred endotracheal tube et of the invention and is seen to comprise an elongate flexible tube 10 which may have an initial curvature between a distal end 11 and a proximal end fitting 12 that is adapted for external connection to conventional gas air monitoring and supply equipment available to the anaesthetist the mention of curvature between ends 11 12 is primarily for purposes of having the et of fig1 be recognized as an et because the thinking and practices of anesthetists have long been conditioned by conventional et devices as having an arcuate appearance moreover the arcuate configuration shown can be understood as an arc in a single vertical plane of symmetry which includes a geometrically central axis designated a a in fig4 as suggested above it is.