I have a Cannondale that came with a FSA stem - I replaced it with a ZIPP. The headset has a threaded internal device that the previous cap had a receptical to screw over and then be able to be drawn down on -the. ZIPP is threadless so there in lies my question and delema
wondering if they are parts for a Carbon steerer fork?
a threaded sleeve, that you have to Epoxy in place .
It is a Blind Guess. I recommend Brick and Mortar Bike shops
where people can see what you are talking about ,
since no picture albums are offered or Mfg Product links..