The FIZZ-X is a very handy and versatile tool. You can use it to aerate your must prior to adding yeast. It eliminates the need to pick up a full 5 gallon carboy and shake or to hand stir it to drive off CO2 and oxygenate your must. Simply attach it to a drill, insert it into the carboy pull the trigger and stir. It designed to be used in 5, 6, 6.5 gallon carboys. It can also be used in fermenting buckets.