Brochure
REDUCE SOUND LEVELS AND IMPROVE 
SOUND QUALITY IN REAL-WORLD INSTALLATIONS. 
Without QStream
™
Technology
With QStream
™
Technology
The innovative, patent-pending 
QStream
™
 technology utilizes 
airflow-smoothing baffles that 
reduce turbulence which means 
the blower can turn more slowly 
and quietly—without airflow loss.
QFLOW
™
 TECHNOLOGY MEANS SMOOTHER AIRFLOW
AND OPTIMAL BACKDRAFT SEALING.
QFlow
™
 Damper Technology Patent-pending QFlow technology helps achieve desired 
building airtightness scores when the fan is off. It also removes the duct damper flap 
from the airstream path, reducing static pressure and noise when the fan is on.
Pre-installed 
screws in the 
mounting frame 
enable quick 
installation
Without QFlow, 
outdoor air can intrude 
past the damper edges.
W
ith QFlow, outdoor air 
intrusion is blocked with 
its edge-to-edge design.
Without QFlow, the flap 
impedes airflow which 
increases static pressure, 
turbulence and noise.
With QFlow, the flap lifts out of 
the way, minimizing turbulence 
for more quiet operation.
FAN OFF FAN ON
10
ULTRA
PRO
™
 FANS & FAN/LIGHTS










