Duplex Filter Housings A duplex vessel consists of two "separate" bag vessels that share the same inlet and outlet connections.Thus having the capacity to double the flow rate and filtration surface area by utilizing both vessels simultaneously. Alternatively, in applications where a continuous flow (without interruptions) is required, isolation valves are added to direct the flow through one vessel while a bag change - out is being performed on O Filter Type: top inlet or side inlet O Filter housing volume (litre): 32*2