Puff Topography and Sensory Effects Across IQOS Device Generations

Brief Summary

The goal of this clinical trial is to learn how people use two generations of IQOS heated tobacco devices and how each device affects their smoking behavior and sensory experience. The main questions it aims to answer are: * Do participants puff differently when using the newer IQOS Iluma i compared to the older IQOS 2.4? * Does the flavor of the tobacco stick (preferred flavor vs. standard tobacco flavor) affect puffing behavior or sensory experience? * What are the differences in throat hit, mouthfeel, and satisfaction between the two devices? Participants will: * Attend 2 laboratory visits at the American University of Beirut * Use both the IQOS Iluma i and IQOS 2.4 devices during each visit * Have their puffing behavior recorded automatically during device use * Provide a breath sample before and after each use session * Complete short questionnaires about how each device felt and their urge to smoke