Attach 2' of 1/4" tubing from the "gas in" dip tube inside the keg. (Tubing not included). You set your desired pressure on the regulator and gas gets emitted through the .5 micron stainless stone. The half micron bubbles rise through the beer creating so much surface area contact between gas and liquid that the absorption rate is very rapid. This is very similar to how beer is carbonated in breweries. You can also use this stone with an oxygen source to oxygenate the wort pre-fermentation. Use 6-8 PSI or until you can see bubbles for wort aeration. Great carbonation stone