In this arm, subjects will receive tobacco flavor- without nicotine (placebo). Participants will then be exposed to 3 levels of a menthol additive in random order: no dose, low dose and high dose.

In this arm, subjects will receive a low dose of nicotine (6 mg/ml) added to the tobacco flavor. Participants will then be exposed to 3 levels of a menthol additive in random order: no dose, low dose and high dose.

In this arm, subjects will receive a high dose of nicotine (12 mg/ml) added to the tobacco flavor. Participants will then be exposed to 3 levels of a menthol additive in random order: no dose, low dose and high dose.

Participants will receive no nicotine, low dose nicotine (6 mg/ml) or high dose nicotine (12 mg/ml)

The Drug Effects Questionnaire (Soria et al) will be used to ask about participants' liking/effect of the e-cigarettes smoked during the 4 bouts of e-cigarette puffing during the lab session to determine which menthol dose is most preferred. A linear mixed-effects regression model wil be used with nicotine group (none, low, high) as between-subject factor, and menthol dose (none, low dose, high dose) as within-subject factor.

E-cigarette value will be determined using the Multiple Choice Procedure (Griffiths et al, 1993) to determine the reinforcing value of the e-cigarette. The MCP involves sampling the e-cigarette and then making a discrete choice between the e-cigarette or a series of monetary values.