Ultegra: RD-R8050, RD-RX800, RD-R8000, RD-6800, RD-6600, RD-6603, RD-6700, RD-6703, Di2. XTR: RD-M9000, RD-M970, RD-M981, RD-M986. NEWOMNI Racer Ti Ceramic Bearing Derailleur Pulleys. If your looking for all the extra edge you can get, these are for you.
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