The EcigAero provides an important tool for studying the acute effects of vaping electronic cigarettes (ECigs) and the chronic effects of multiple ECigarettes a day for long periods of time by repeatedly exposing rodents to ECig aerosol in a home cage-like environment. Our system provides a powerful toolkit for in vivo studies of ECig effects on cardiovascular, respiratory and nervous systems, metabolism and carcinogenesis as well as facilitating new therapeutic discovery. Key Features - Direct delivery for ideal aerosol - No tubing, bends, mixing chambers, fans or pumps between the ECig and the rodent chamber. Aerosols deteriorate rapidly during transport and dilution when passing through tubing and chambers due to droplet coagulation, condensation and vaporization. We have characterized the particle size distribution of the ECig aerosol in our chamber†. The EcigAero maintains consistent aerosol characteristics to those at the mouthpiece where humans inhale ECig aerosol. The pulmonary distribution of the aerosol generated in this device correlates with that generated by ECigs during typical human use. Multiple "real" electronic cigarettes - The EcigAero will accommodate up to four (4): First generation Blu PLUS+ ECigs (battery powered), Second generation JUULpods™ or myblu™ Liquidpods, Third generation "mod" tanks with universal "510" industry-standard threads. Can be used along with any aerosol via nebulizer (optional). The aerosols are delivered at a highly regulated pressure with a flow rate between 0 and 4 liters per minute (LPM). Pods and tanks are precisely energized with 0.1V accuracy. The EcigAero tests the inhalation exposure of REAL ECigs rather than de novo generated mixtures of nicotine + E-liquid. The exposure doses of our rodent models were verified by plasma nicotine levels/PK and with our software can be controlled by varying the number of ECigs simultaneously activated, puff duration, inter-puff intervals and frequency of puffs. The capacity for multiple ECigs allows for longer experiments than a single ECig battery or tank, Higher concentrations of aerosol if multiple ECigs are delivered simultaneously, Side-by-side testing of different ECig flavors or nicotine concentrations.