The ironic thing here is that traditional duct tape should _not_ be used for attaching HVAC ducts together. The adhesive doesn't withstand the temperature extre

The ironic thing here is that traditional duct tape should _not_ be used for attaching HVAC ducts together. The adhesive doesn't withstand the temperature extremes, and it has undesirable properties if it catches on fire. UL-listed foil tapes are used for this instead. It seems like cloth-backed tape started as "duck" tape (as in duck cloth), somehow turned into "duct" tape, and then turned back to "duck" for marketing purposes. It has quite an odd history.