The removal of traditional mechanical cables in favour of electrical wires not only eliminates poor shifting caused by contaminates corrosion & stretching but provides effortless gear shifts Ultegra Di 2 uses a fully removable individual cable system from the battery indicator junction box enabling fine tuning with the correct cable length to each component for easy & tidy fitment This kit contains SM-JC40 bottom bracket junction SM-BMR1 long external type bottle cage battery mount EW-SD50 individual wires: 1X 1000 mm 1X 500 mm 2X 300 mm & SM-EWC2 black stick on wire covers: 3X 300 mm 3X 50 mm Ultegra Di 2 also requires a handlebar cable set to connect the shifters to a battery indicator junction box &40;comes with handlebar cable&41; External cable sets are ideal for upgrading your current bike to Ultegra Di 2 if it does not feature the internal cable routing option EW-SD50 individual wires are available in varying lengths there is no need &40;or facility&41; to cut these cables Reliable & secure water resistant connectors