Check the listing for details. Shimano SM-JC41 Di2 Internal Frame Junction Box 4-Port. Condition: New. Listed at 28.99 USD. Powered by Frooition Shimano SM-JC41 Di2 Internal Frame Junction Box 4-Port Item Description Shimano Di2 Frame Junction Box Frame Junction Box connects via SD50 E-tube wires to four different points: front derailleur, rear derailleur, cockpit junction box and battery mountAll Di2 components on the bicycle require the same firmware version. Using Di2 components with different firmware versions may cause malfunctionsUse Di2 system checker to update component firmware from https://e-tubeproject.shimano.com/ $28.99 NEW Shimano Powered by Frooition Frooition Frooition | No-js Template | eBay design, eBay store design, eBay shop design, eBay template design, eBay listing design (ver:froo_no_js) This listing is currently undergoing maintenance, we apologise for any inconvenience caused.