This is the Shimano Di2 SM-BCR2 Battery Charger for charging the battery on all Shimano Di2 electronic shifting systems with an internal battery. Features: SM-BCR2 Internal battery charger is specific to the SM-BTR2 internal battery (BA9070) Plugs into SM-EW90 cockpit junction boxes or SC-S705 display unit Includes USB (SM-USB1) power adapter For use with Alfine Di2, Dura-Ace 9070 and Ultegra 6770 equipped bicycles Use with PC to update Di2 component firmware and change system functions For use with Alfine Di2, Dura-Ace 9070 and Ultegra 6770 equipped bicycles All Di2 components on the bicycle require the same firmware version. Using Di2 components with different firmware versions may cause malfunctions Use Di2 system checker to update component firmware from http://e-tubeproject.shimano.com/ Specifications: FD/Shifter Compatibility: Dura-Ace 7970 Di2 FD/Shifter Compatibility: Dura-Ace 9070 Di2 FD/Shifter Compatibility: Shimano Ultegra Di2