Fenner's Powertwist belts are pricey; but they work great at dampening vibration on machinery. My tablesaw used to dance like a bad stripper when I shut it off. I put a Powertwist on it and the dancing stopped.
The belts are unidirectional and I think the separate links act to localize vibration instead of transmitting it throughout the belt. Also it's nice to be able to make a belt the right size for the machine.
I asked Fenner if they would work on lawn tractor mower decks and they didn't recommend it.