Shimano Altus Rear Derailleur RD-M310-L 7/8 Speed Bike Bicycle Cycle

M310 Rear Derailleur. Shifter/Derailleur Compatibility: Shimano. Cassette Spacing: Shimano/SRAM 8. Pulley: 13t upper & 15t lower. Chain Wrap Capacity (teeth): 43 teeth.

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