Costume question - concert Kate's belt buckle?

It's been over a year since you asked, but I thought then and am still pretty convinced now that it is a child's or adolescent's toy. My brother had one, and I don't remember what it went to, but there were these orange plastic discs that looked like gears that you slid into a slot and then they could be fired out. Knowing my brother, it was maybe some kind of war or military thing. It was too early for Transformers, but probably something like that. Maybe G. I. Joe? Anyway, pretty sure it was that toy that had been stuck on a belt.

Wow...I retract my suggestion; I haven't watched RnRHS in a while, so I just played it. I must have never really looked before, because whatever Kate has on her belt isn't what I thought I saw. So...I don't know. Sorry.