I purchased a Plumb Craft stop leak replacement flapper.
The original flapper connected to two posts on the water return pipe.
This flapper has no place to attach it to the pipe.

Is it held in place by the lower portion of the flapper sticking to the supplied adhesive ring?

Thanks.

If this is the Plumb Craft flapper you purchased (see image) then it's adaptable. Simply cut the ring out (see image) Good luck, Tom

If you are using the cup type replacement flapper and lower seal, it pivots on the base, not the tube.