Rodent Containment System may be used as an open or closed system. If an open system (free flow or air) is desired, align the holes on the top cone with the main clear cylinder. If not, realign the holes to affect the closed system. Once realigned, simply tape the top and bottom to the main cylinder. Applications include metabolism studies, CO2 collection, inhalation work, euthanasia chamber, isolation requirements and anesthesia techniques.