Pico wrote:
(. . .) I haven't found any that was the same as the stuff we used in the
early Seventies. This is not a case of selective memory. The original stuff
could be folded over on itself into a small square and stuck in the pocket
for odd emergencies outside of work. It unfolded nicely without leaving
residue in itself and would work again. (. . .)

Sounds like what others of us in the same era referred to as "racing tape",
suitable for body work, patching an exhaust manifold, or (rolled up) a
(non-functioning) substitute for a spark plug. :-)