Rather than use a propylene glycol solution, the iQOS relies on replaceable real tobacco leaf cartridges which are shaped like conventional cigarettes. These "heat sticks" plug into the plastic heating element to produce a 500 degree F vapor and last around a dozen puffs.

If approved, the iQOS could profoundly shake up the US vaporizer market, which is currently dominated by modular, e-liquid-based vapes. The iQOS' ease of use, low cost (heat stick packs cost around $6 on average), and brand familiarity are a potent marketing combination. The iQOS is already being sold in a number of foreign markets, including Japan where it has already captured nearly 2.4 percent of the market there.