A dual-colour adapter designed for a Creality CR10-S, but should work with all "standard" Creality extruders. I think they all use pretty much the same one? Uses the Bowden adapters that come on a Creality extruder. They're these ones:https://www.banggood.com/Creality-3D-5PCS-3D-Printer-M6-Thread-Nozzle-Brass-Pneumatic-Connector-Quick-Joint-For-Remote-Extruder-p-1192667.html This needs about 32mm of Bowden tube inside it. Pop it in your hot-end and trim flush with the top of the red metal, then slide it back out and push it into the printed part. Then push the whole lot onto the top of the hotend and mount with some longer m3 screws. I use PrusaSlicer and I've included a screenshot of the material change settings I use (the large screenshot is in the Filament Settings and the small screenshot is in the Printer Settings).