Marco DWF36F-2 Pipe?

[chemist101]

I'm looking to get information about marco pipe since I need to redo the siding and chase cap replacement on my house. I figured I could redo the piping as well since everything would be open but can't find any information about what would be an alternative to the 8DN (not 8DM) parts which now all seem to be discountinued. I also need this to order my chase cap since I don't know the OD of the piping and really don't wanna climb on the roof to uninstall for measuring.

Anyone have any insights?

 

[begreen]

If this is on a Marco fireplace the chimney pipe may be proprietary with no modern replacement. The Marco DWF36F-3 used double-wall air-cooled chimney pipe. I don't know of any substitute.