Attach the Sterile Siphon starter assembly by firmly pushing the carboy hood over the mouth of the carboy. Slide the stainless racking cane to the desired depth, just about the sediment level and blow into the white, sanitary air filter for 2-3 seconds until you have a solid flow of beer running out the tubing. There is no need to worry about contamination from your mouth, as the sanitary filter removes 99.98% of airborne bacteria. Works on all carboys. Specify threaded or smooth carboy.