Just the core! For a long time, creative fingerboarders have been carefully dissecting their dual durometer wheels to get just the small inner core as a wheel. Now, you don't have to do that, and you can save a few dollars too!
Please note that these wheels do have a small ridge on the riding surface. This is literally just the inner core with a bearing, not a specially designed smaller wheel. Just due to getting so many requests, we've decided to offer a few sets!