Originally Posted by
WhyFi
Just shave the top of the steerer another mm and you'll be fine.
The thing with the patent number on it is an expanding plug - it holds on to the inside of the steerer and acts as an anchor for when you're adjusting preload against it with the top cap.
If it was just the expanding plug then it wouldn't have a hex bolt head in it.
I'm not 100% sure. I'd need to check it out in person to know for sure, unless someone else really knows for sure.