Oooooooo.
That hits the spot.
I'm always so jealeous of women in tit clamps as I'm so flat.
I do have something like this in steel that I had to get made (Very narrow so there is enough flesh to pull through, taller to give strength.) The pain is intense as the edge is so narrow, focused. I'm bruised for 3-4 weeks minium, and haven't used them in a while. Not thought to incorporate a nipple-noose like that (Clamps usually). Will have to ponder this for the next time I really deserve it.