Shimano did it right when it came to designing the new Ultegra Di2 wiring setup. It's slimmer and has smaller connectors than the Dura-Ace Di2 system, giving your bike a cleaner look with less messy wiring. You can also run these wires internally or externally, as long as your frame is compatible with internal wire routing. This wire is waterproof and easy to install with the new junction box design. Just plug it up and hit the road.
Item No. » SH-SD50S
Nashbar: $29.991 or more: $29.99