Tapered rubber stopper to effectively seal carboy mouth for beer fermentation. Made of food safe material, the stopper has a drilled hole at the center. This can be used to hold the air lock – another fermentation accessory that allows a one-way gas exchange. CO2 gas from yeast activity is released while not allowing any gas to enter the fermenter.
This is a medium size sealing stopper. We also offer the same in small and large sizes as well.