The small round plastic part is the slow speed needle "bearing". It goes way deep in the hole, where the straight part of the needle resides. Bearing is sort of a misleading name, It actually is a "seal" to prevent air from sucking in past the threads. I had a home-made puller to get it out, back in "The Day". Others have used some sort of a hook. Others have used a drywall screw. Others have just left it alone and hoped for the best.
The friction bushing is the larger part with a tab on one side, at the entrance to the needle.