I bought this at a general store and only used it that day, so I'm selling it. I only remember using the jagged one (it was the only one that fit...). I think the sizes are slightly different, so it might be for various fingers, but in my case, only my pinky finger fits, so I'm listing it as a pinky ring. The simple one seems a bit larger in diameter, but thanks to the shape, the jagged one goes all the way to the base of my finger. Thank you.