Hello, I have a Fisher mama bear with a six inch rear opening. I was wondering if there is an adapter or something I need coming out of back before installing elbow? It seems as though the six inch crimped male end of the elbow I tried would not fit in. It seemed impossible to insert. Any help would be greatly appreciated. Thank you.
![[Hearth.com] Fisher Mama Bear Install Question [Hearth.com] Fisher Mama Bear Install Question](https://www.hearth.com/talk/data/attachments/146/146226-34ce7e4f1981de33ef4c89606c422a73.jpg?hash=XfRutFFik7)