That looks like they went with a 10 or 12-flat instead of an 8 (octagon) in order not to have to cut so much material from the ring.
Probably looks better than an octagon ring if I can imagine what one would end up looking like.
Kind of a 60's custom metal look though to me no matter the # of flats,,I'd prefer the square bridge look.
Classics are always in style.
But everyone is entitled to their own,,that's what custom is all about.
But that's also why resale of your own pet project ideas can be so difficult too.