Please Help me ID this Plastic Gasket
In the photo, it almost looks like fiberglass cloth. If your coach has had a new tank installed in the past, it may be part of the kit that was used to fiberglass the toilet flange into the tank. I know that was one of the processes the tech described to me when I picked up my Overlander after having a new blackwater tank installed on it last month. The new tank from Airstream was produced without the cutout for the toilet so that the tank could be used for several models of Airstreams which meant that the opening for the toilet had to be cut in the field.
Another thought -- could it possibly be some type of screening that may have been over the bathroom vent fan? This is a long-shot but the shape would be approximate if your Airstream as the little circular roof-mounted bathroom vent fan like my Minuet.
Kevin D. Allen
WBCCI (Lifetime Member)/VAC/Free Wheelers #6359
1964 Overlander International/1999 GMC K2500 Suburban (7400 VORTEC/4.11 Differentials)
1978 Argosy Minuet 6.0 Metre/1975 Cadillac Eldorado Convertible (8.2 Liter V8/2.70 Final Drive)