Shimano Dura-Ace ST-R9180 Di2 TT Shift/Brake Lever with Wire - Right, 11-Speed, For TT Bars, Black. Single button on each side of the shifting lever only works with Shimano Synchronized Shift. MPN: ISTR9180R - Shimano - Dura-Ace ST-R9180 Shift/Brake Lever - Brake Lever, Drop Bar Individual.
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