Pipelyne has them and they are made of quality carbonium friction material (same clutch material used on high end Polini and BZM pocketbike motors) So the material has been tested and proven to be duriable on the track. Your first set will probably be your last set. Out of the many people that bought them, everyone has been extremely happy.
Give Pipelyne a call.
(408) 279 2307
Clutch Pucks