all weatherstrips not 'sponge rubber' would be vulcanized in that one sense Tim, note in the Steele catalog that the only parts specifically stated to be 'vulcanized' are window seals that are one closed loop, not the open-ended ones - their use of the term indicates the ends of the seal have been "heat set" [not glued] together [the 'physical process'] .... as they stated when I discussed the original barn door weatherstrips I supplied for them to repro - the "loop" isn't cast in one piece, it's extruded, then made into the correct closed shape, in the case of the TF door rubbers,
the joints are at the square corners - the 2nd door only has the seal on 3 sides
I see 'vulcanization' actually has a: "2. The cross linkage of an adhesive substance obtained by the application of heat and catalysts"
Bill