A tubular member (42, 62) of the type commonly utilized in wellhead equipment (10) having embodied therein sealing means (72, 64) operative when cooperatively associated with a mating member (16, 14) to effectuate the establishment of a fire resistant seal between the tubular member (42, 62) and the mating member (16, 14). The subject tubular member (42, 62) preferably terminates at one end thereof in an extended neck portion (82, 80) with the sealing means (72, 64) being provided on the outside circumferential surface of the extended neck portion (82, 80) adjacent the free end of the latter. The mating member (16, 14) includes an inside circumferential surface suitably dimensioned such that the tubular member (42, 62), when inserted therewithin, can be made to occupy a fixed longitudinal position relative thereto. The sealing means (72, 64) includes an annular band (74, 66) embodying preselected height and width dimensions, the ratio of which falls within a predetermined range such that when the tubular member (42, 62) and the mating member (16, 14) occupy the aforesaid fixed longitudinal position thereof the engagement of the annular band (74, 66) of the tubular member (42, 62) with the inner circumferential surface of the mating member (16, 14) establishes an elastic but fire resistant seal therebetween characterized by the fact that plastic deformation is avoided yet the required unit loading is furnished thereby.