You might be thinking, "I'm not selling to engineers; why do I need to know this?" Because the details that make a vape work are the same details regulators care about. Battery capacity determines how long a device lasts and whether it might overheat. Coil resistance affects how much power is drawn and how much vapor is produced. The e-liquid composition determines nicotine strength and flavor.

If any of these specs are off from what's stated on the label, that's a compliance problem. For example, if a device claims 5% nicotine but actually delivers less, users might be getting less than intended—or more, depending on how the coil interacts with the liquid. Either way, it's a mislabeling issue.