The PRR-CD plenum boxes connect the ductwork ends to
the NCD round supply diffusers in low- or medium-pressure
ventilation systems.
A plenum box stabilizes the air supply, providing uniform air
flow rate before the air enters the diffuser. The ductwork is
connected to the plenum box inlet port at the side or from
above, depending on the product type. The inlet port can be
provided with a damper.
