Shimano Deore XT RD-M786-SGS Shadow + Rear Derailleur - Black - Long Cage. 40T (42T for 1x 11-speed) capacity SGS cage. Shimano GRX Rear Derailleur Shadow+ RD-RX810 - 2 x 11 Speed. Shimano GRX Rear Derailleur Shadow+ RD-RX812 - 1 x 11 Speed.
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