Features: 80 CFM centrifugal blower, specifically designed for continuous use application EZFit™ features make installation a breeze Extremely quiet 1.1 sone operation Rugged, galvanized steel construction Short housing height allows for installation in 2 x 6 inch ceilings Alternate installation allows housing to directly attach to ceiling jousts or trusses White polymeric grille harmonizes well with most bathroom decor UL listed for use over bathtubs and showers when using a GFCI protected circuit Energy Star and HVI certified Patent-pending designProduct Technologies: Mid Sones: We know that comfort and ambience matter in your bathroom. This fan produces 1.1 sones of sound output, keeping the noise in your bathroom at a reasonable level. Low CFM Capacity: This fan has an efficient 80 CFM (cubic feet per minute) of clearing capacity designed for smaller bathrooms. Controlling humidity in your bathroom extends the life of your décor and makes for a more hospitable space to prepare for the day ahead. Specifications: CFM: 80 Sones: 1.1 Duct Size: 3 Inch Round or 4 Inch Oval Grille Width: 13 Inches Grille Length: 14-1/2 Inches Housing Length: 12" Housing Width: 10-1/2" Housing Depth: 5"