The stainless steel diffusion stone can be used with "fish tank type" air pumps or pure oxygen regulators to aerate wort. You can also use this stone for carbonating. Attach 2' of 1/4" tubing from the "gas in" dip tube inside the keg (tubing not included). You can set your desired pressure on the regulator & gas gets emitted through the 2 micron stainless stone. The 2 micron bubbles rise through the beer creating so much surface area contact between the gas & liquid that the absorption rate is very rapid. This is similar to how beer is carbonated in breweries.
Oxygen Diffusion Stone - 2 Mic
$11.99