HVI certified rating at 0.1SP for: QCF200 = 200 CFM & 4 sones ,QCF300 = 280 CFM & 4 sones , QCF400 = 350 CFM & 4 sones ,QCF500 = 500 CFM & 4 sones ,QCF600 = 640 CFM & 5.5 sones , QCF800 = 690 CFM & 6 sones