from williamsbrewing.com (22" aeration wand):
This stainless air stone on a 22" stainless steel tube is ideal for aerating wort before fermentation. Features a 2 micron air stone that is permanently affixed to a 22", 3/16" outer diameter stainless steel wand. . Fits standard aquarium air pump tubing. Easy to clean by soaking in diluted Star San solution or by boiling for 5 minutes. The stone is 1/2" wide by 1" long.