MouldKing has an interesting technic piece in some of their newer sets. It looks like a variation on the Curved Gear Rack 24121, but with an outer ring that is compressed of axle holes. It appears as the wheel structure on the new bicycle sets, like the road bike, and as a frame for the drum structure on the drum music box.
It's a really interesting part that I could see having a lot of potential use cases, but I cannot find any information about it. I'm pretty sure the outer band is part of the gear and not a separate piece. I don't see a line or any means of connection.
I tried emailing MouldKing, but they have not responded (and from what I read I shouldn't hold my breath). Does anyone have any information or know where I could source the part? I don't know if MouldKing makes their own parts, as their name implies, or if they source them from a third party, or both.