Carboy Bung Retainer

This is a bung retainer I designed for my carboys, for use when making homemade wine, mead, or anything else that needs to have an airlock installed on a carboy. It is held together with rubber bands to maintain pressure on the bung.

The sizes are listed by the gallon volume of the carboys I own, and carboy designs may vary a bit, so go by the dimensions of your carboy, not the gallons I have listed. The “topper” is universal.

Here are the internal dimensions of all of the sizes:

1 gal: 44.0 mm neck

6 gal: 48.0 mm neck

6.5 gal: 42.7 mm neck

Topper: 12 mm stem, 48mm OD