Shimano Shimano Di2 E-Tube 4 Port Junction B - (SM-JC40 or SM-JC41)

Shimano Shimano Di2 E-Tube 4 Port Junction B - (SM-JC40 or SM-JC41)The Shimano Di2 Junction B box is the center of the e tube Di2 system. All of the component and battery wires meet here before running out to their respective components. All of the wires that connect to the junction box use the same connector to make assembly that much easier. Choose the SM JC40 External box if you are running your wires on the exterior of the frame or choose the SM JC41 internal box if you are running your wires inside your frame.

Running - Reloaded

The wrap-around eye shield offers an unblocked field of view with a huge aerodynamic benefit and the shield is made by ZEISS Optics for unrivaled clarity

So whether you're hammering off the front

Extra-wide platform for a more efficient transfer of power

not paired to any apps) lets you ride with a progressive resistance curve that matches the Fluid2

durable vinyl exterior material to withstand wear

Easily regulate flow of CO2 air with a turn of the control knob and top off your tire pressure with the dual-action hand pump

Orange Oil

Biodegradable ultra slippery formula

Constructed using a seamless pattern of performance materials

Touring Plus

Aero-weenies rejoice with 50% drag savings