This project will assess the ways in which e-cigarette product diversity impacts the user experience to inform potential regulations by identifying product characteristics that may: (1) put young adults at risk for tobacco product use; and (2) facilitate adult smokers switching to e-cigarettes. There are three primary objectives to the study: (1) Determine which dimensions of e-cigarette product diversity differentially affect product appeal in the overall population of tobacco product users as well as affect product appeal across young adult e-cigarette users and middle-age/older adult smokers; (2) Determine which dimensions of e-cigarette product diversity differentially affect product appeal in the overall population of tobacco product users as well as affect abuse liability in young adult e-cigarette users and the ability to resist smoking in adult smokers; (3) Determine the affect of product characteristics on e-cigarette nicotine delivery profile. For this substudy, young adult vapers (N=100) and adult smokers (N=100) will attend one laboratory session in which they will self-administer e-cigarette products varied according to within-subject e-cigarette factors (e.g., flavor, nicotine formulation).

Inclusion Criteria:

Vapers/E-cigarette Users

• E-cigarette/vaping device use at least three days per week for at least 2 months
• Regular use of e-cigarettes/vaping devices containing nicotine

Cigarette Smokers

• Daily cigarette smoking for at least two years
• Currently smoke at least four cigarettes per day
• Interested in trying an e-cigarette or current use of an e-cigarette

Exclusion Criteria:

Vapers/E-cigarette Users

• Pregnant or breastfeeding
• Desire to cut down on use of e-cigarette/vaping device

Cigarette Smokers

• Pregnant or breastfeeding
• Current daily use of other combustible tobacco products (such as cigars)