Inclusion Criteria:
* Age 50 years or older.
* Currently smokes 5 or more combustible tobacco cigarettes per day and has smoked at this level for at least 1 year, based on self-report.
* Expired-air carbon monoxide level ≥8 parts per million (ppm), confirming recent cigarette smoking.
* Average screening/baseline systolic blood pressure ≥130 mm Hg or average screening diastolic blood pressure ≥80 mm Hg.
* Able and willing to provide informed consent and complete the study procedures, including in-person visits, two 14-day study periods, daily check-ins, and use of study equipment.
* If able to become pregnant (confirmed with participant), agree to avoid pregnancy during the study.
Exclusion Criteria:
* Self-reported consumption of 4 or more standard alcoholic drinks for women or 5 or more for men on any single day during the past 30 days.
Self-reported daily nonmedical use of opioids, stimulants, sedatives, cannabis, or another substance.
* Currently seeking or receiving smoking-cessation treatment.
* Currently uses another tobacco or nicotine product (e.g., electronic cigarettes or smokeless tobacco) on 2 or more consecutive days during the past month.
* Currently taking medication for the treatment of hypertension.
* Experienced a major medical event, including a cardiovascular event, within the past 6 months, such as myocardial infarction or acute coronary syndrome, stroke or transient ischemic attack, coronary or peripheral revascularization, hospitalization for heart failure.
* A current unstable cardiovascular condition that, in the judgment of the PI or designated medical clinician, would make participation unsafe.
* Confirmed severe hypertension at screening: resting systolic blood pressure greater than 180 mm Hg OR diastolic blood pressure greater than 120 mm Hg on repeat assessment.
* Pregnancy, as indicated by a positive screening urine pregnancy test conducted for a participant who reports being able to become pregnant.
* The investigator or medical monitor determines that participation would present an unacceptable medical or safety risk (i.e., current concerning cardiovascular or neurologic symptoms; an acute or uncontrolled medical illness; clinically significant intoxication or withdrawal; a medication or health change likely to make blood pressure, heart rate, or study participation unsafe; inability to safely use the study equipment despite training; or another specific condition that creates a foreseeable risk from continued smoking, e-cigarette exposure, or study procedures)
