This adapter makes it possible to connect standard soda bottles directly to Sodastream carbonator. Use a seal from a normal bottle cap, an o-ring or something else to properly seal the soda bottle properly to the adapter.
Model is made with a little tolerance. It printed perfect as is on a Robox from PLA. I assume it's safe to use this in the kitchen as it doesn't get in touch with the water being carbonated.
Original FreeCAD and Cubify Design files are included in case modifications for a different kind of bottle thread or neck needs to be done.
Version 5 has better threading for the bottle, but I still wouldn't recommend using this.