This adapter will screw on to the top of any paintball CO2 tank.  With the adapter on, you can then screw the paintball CO2 tank in to your Soda Stream machine effectively converting your Soda Stream machine to use paintball CO2 bottles.

The adapter has an adjustment screw at the top which may require minor adjustment for some machines.

Paintball tanks are easy and cheap to refill when compared to the proprietary Soda Stream tanks and they come in a variety of sizes.  A 12oz (or smaller) paintball tank will fit in most machines.  If you have a larger machine like the Fountain Jet, Edition I, Dynamo, Fizz, or Revolution then you should be able to us up to a 20oz paintball CO2 tank.

This is a Female .825x14 NGO thread to Male Soda Stream coarse thread adapter.