This is a proposed double-blind, crossover study that enrolls young adult smokers who prefer menthol cigarettes. The study will consist of an adaptation session and three test sessions. In the adaptation session, participants will practice using the e-cigarette by sampling the flavors to be used in the test sessions. The test sessions will be performed following overnight abstinence from tobacco. Across the three test sessions, participants will be assigned to a random sequence of the three different e-cigarette conditions: menthol, green apple or menthol plus green apple, a different flavor condition for each test session. In each test session, just after the assigned flavor is delivered via the e-cigarette, participants will receive a random order of one intravenous delivery of saline, and two intravenous deliveries of nicotine (3.6 mcg/kg and 7 mcg/kg or 0.25 mg/70 kg and 0.5 mg/70kg), one hour apart. The test sessions will be performed at least 24 hours apart to minimize carryover nicotine effects. The main outcome measure will be subjective drug effects as measured with the Drug Effects Questionnaire (DEQ). Other outcomes include cardiovascular measures, cognitive performance, and self-report measures of nicotine withdrawal and craving. Cardiovascular measures include heart rate, systolic and diastolic blood pressure. Cognitive performance will be assessed with the Stroop test, mathematical processing test (MPT), and continuous performance test (CPT). Nicotine withdrawal measures will be measured with the Minnesota Nicotine Withdrawal Symptom Checklist (M-NWSC) and the Brief Questionnaire on Smoking Urges (BQSU).