Shimano Part Number: Y3FW98020. The Shimano bracket axle unit for Deore XT RD-M8100 & RD-M8120 12-speed rear derailleur. Deore XT RD-M8100. Deore XT RD-M8120. Shimano RD-M8100 & RD-M8120 Bracket Axle Unit.
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