Broan 509S Through-Wall Fan with Integral Rotary Switch, 8-Inch 180 CFM 6.5 Sones 180 CFM 6.5 Sones Includes on/off rotary switch - no wall switch to wire Housing adjusts to fit walls from 4-1/2-Inch to 9-1/2 thick and has a 8-3/8-Inch diameter sleeve Specially designed polymeric fan blade Built in damper minimizes back drafts for energy efficiency 180 CFM 6.5 Sones Includes on/off rotary switch - no wall switch to wire Housing adjusts to fit walls from 4-1/2 inches to 9-1/2 thick and has a 8-3/8-Inch diameter sleeve Specially designed polymeric fan blade Built in damper minimizes backdrafts for energy efficiency