A:AnswerHi Barry, thank you for your question and interest in Model:DUH36152UC. The 300 Series is 280 CFM with incandescent lights and three power levels. Here is the link for the Specification Page for the DUH36152UC: https://files.bbystatic.com/f9ptZt4E0wJnCKb67wG%2BtQ%3D%3D/SPEC%2BSHEET
The 500 Series is 400 CFM with halogen lights and four power levels. Here is the link for the Specification Page for the Model: DUH36252UC:https://files.bbystatic.com/rzUxVZHua%2Fxg90wsmKtimw%3D%3D/SPEC%2BSHEET
Both can be ducted or recirculating.
