The Shimano SM-EW90-B shock box (Junction A) acts as the central unit of the Di2 system, connecting the gear levers and other electronic control units via five ports. The jewel case includes a battery charge indicator, a charging socket and an indexing control switch. It mounts under the handlebar bracket and is compatible with the Di2 E-Tube system.
Five-pin Di2 junction box for connecting multiple components, integrated display and charger.
The Shimano SM-EW90-B shock box (Junction A) acts as the central unit of the Di2 system, connecting the gear levers and other electronic control units via five ports. The jewel case includes a battery charge indicator, a charging socket and an indexing control switch. It mounts under the handlebar bracket and is compatible with the Di2 E-Tube system.
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