Allows the Paramount Ductless Enclosure to be thimble-ducted to the outside for additional protection. The canopy's air gap provides a means of balancing air by allowing room air to enter the ductwork and mix with the filtered air being exhausted from the Paramount. House exhaust or remote blower and ductwork are required (not included). 6" (15 cm) diameter outlet. 6' Paramount Enclosures require two Exhaust Transitions. Requires installation.