FastRack Drilled Rubber Stopper (10 - 3 pieces) Solid Rubber Stopper Bungs for use with Fermentation Airlock Durable Carboy Bung Tapered Bung for Corking Home Brewing Glass Carboys.

This is a drilled Tapered rubber bung for a better seal and holds the airlock securely in place. A curved lip stops the bung from accidentally falling into the carboy. All three rubber stoppers are the same Size and easily fits all 3, 5, 6 and 6.5 gallon glass carboys. These stoppers do not fit plastic carboys or plastic water bottles.