ROCKBROS Rear Derailleur Carbon Fiber Cage Pulley Kit 17T For Sram Di2 Style

SRAM Di2 : SRAM Etap Derailleur System. 17T Oversized Pulley Wheel System. 17T Big Guide Wheel. Carbon Fiber Bicycle Derailleur Kit. colour:black,ren,green,blue. Net weight: 71g. AL7075 Lightweight Pulleys Wheel.

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