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 file is included in case modifications for a different kind of bottle thread or neck needs to be done.