That link is the wrong cable for the M2 or M2S motor. That only fits the M1 Avinox Motor.Yes it is there, but only e-bikes that are equipped with an electronic SRAM Eagle Transmission connected to the Avinox drive unit with the AXS power cable (00.3018.418.001) can use the Smooth-Shift option. Its about $120 from Fanatik AXS Extension Cord - Eagle Transmission
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