Product review (4 stars): The 7" exhaust fan hole made it a pain to ...
The 7" exhaust fan hole made it a pain to install, could not find a reducer for 7" to 5" to match my stack at Home Depot or Lowes so I had to reduce it twice and shorten my exhaust stack because of the added 9" length of the reducers. This should of been a simple 1/2 hour job not all the time and  modifications...order the reducer when you buy this item.