• SD50 ports: 1. You plug in the EW-SD50 in one end, the EW-SD300 in the other end. This way you can connect current and future Di2 components to each other. Use with the 12-speed Di2 and SM-PCE02. If you want to update the firmware on 12-speed Di2 components, you'll need to use the SM-PCE02 tool.