Delta BreezSmart SMT130H 130 CFM Exhaust Fan with Adjustable Humidity Sensor and Speed Control An indicator light underneath the grille assures you that this quiet fan is running Adjustable humidity set points between ~50% to ~90% RH When humidity is above the user-adjustable set-point, fan runs at full speed (130 CFM). When humidity is below the set-point, the fan runs continuously at a pre-set lower level (0, 50, 70 or 90 CFM) ENERGY STAR Most Efficient for efficient cost-saving operation