The eFlow-Alize Constant Airflow Regulator is a two-in-one constant airflow regulator (CAR) and grille combo. This is a new generation of self-adjusting CARs which provides the perfect match between high technical performance and aesthetic design. This innovative technology offers two models: single airflow and dual airflow. The eFlow-Alize CAR is a factory-set constant airflow regulator designed to save energy by precisely controlling airflow regardless of static pressure, and overall provides high Indoor Air Quality (IAQ). These CARs are designed to operate in pressure range 0.2-inch w.c. to 0.6-inch w.c. They automatically adjust for variable duct pressure caused by building pressure, thermal stack effect and other variable factors. This Constant Airflow Regulator creates a cost-effective answer to balancing air systems for HVAC and ventilation in high-rise buildings, without the requirement of onsite balancing, electric controls or sensors.