Use this filler for bottling from a draft system. Counter pressure filling is how breweries bottle their beer in order to minimize C02 loss. With this stainless steel filler you can bottle beer from a keg, eliminating the yeast sediment on the bottom (and having to explain to friends why it's there). Simply insert filler tube with rubber stopper into the bottle. Fill the bottle with C02, then fill with beer while adjusting the pressure relief valve to let out the C02 you are displacing. Cap immediately, and you're done.