A Buon Vino carboy bung is a must-have for any homebrewer who is serious about achieving first-rate fermentation. The extra-long taper helps this handy bung create an airtight seal to keep oxygen away from your fermenting brew and the protruding lip prevents your Buon Vino bung from falling into your carboy. The pre-drilled airlock hole fits both "S" type and cylinder airlocks and this bung shares dimensions with a traditional #7 rubber stopper. It fits 12, 18.9, and 23 liter carboys. Please note: Also available without an airlock hole by clicking here. Features: Made of rubber. Extra-long taper to create a tight seal. Protruding lip to prevent accidental drop into carboy. Same measurements as #7 rubber stopper. Fits 12, 18.9, and 23 liter carboys. Specs: Dimensions: 1-3/16" Bottom diameter.