Carboy Bung (Silicone) - Breathable

Carboy Bung (Silicone) - Breathable

Item currently out of stock

This high quality Silicone Stopper gives a great airtight seal while still allowing gasses to escape. 
Fits 3,5,6 & 6.5 Gallon glass carboys and 500ml flasks. This breathable Silicone Carboy Stopper acts as both a solid stopper and an airlock. The unique design allows CO2 pressure to escape but keeps oxygen and airborne contamination out. Beer makers love using it during the ferment because it creates a vacuum when the wort cools, instead of pulling water in from your traditional airlock. The airtight seal is great for extended lager fermentations when CO2 production is still present but only very slightly. 
Measures 1 1/2" wide at the top and 1 1/8" at the bottom.
You may also want to check out our Premium Breathable Silicone Carboy Hood.
Item # FE479
Shipping Eligible for Free Shipping Program
Availability Out Of Stock
Weight 0.10 LBS
Community Q&A

Start typing your question and we'll check if it was already asked and answered. Learn More
Browse 4 questions Browse 4 questions and 59 answers
Why did you choose this?
MoreFlavor Store
The best carboy stopper period.
David V on Oct 12, 2021
It should fit
James Z on Oct 8, 2021
The best carboy stopper period.
David V on Oct 12, 2021
Works with the Speidel Orange Airlock
Dave E on Oct 10, 2021
It should fit
James Z on Oct 8, 2021
Need it for my sampling carboy
Walter S on Sep 2, 2021
So I can bulk age wine without having to check airlock water levels every 2 days.
Emmett H on Jul 22, 2021
Because I wanted it for Father's Day from my kids 🤣
Brian Y on Jun 8, 2021
new air stopper
Rocco T on Apr 28, 2021
Used on a barrel and works well.
Alex A on Mar 24, 2021
Everett S on Feb 26, 2021
sour beer aging
Michael I on Feb 17, 2021
I want to bulk age some high ABV beverages and don't want to worry about keeping water in the airlock. Also, I've been brewing a lot of lagers lately and this is supposed to keep oxygen out during cold crash.
Matt Burns on Feb 9, 2021
Tired of losing wine to dry bubblers
Kevin O on Jan 15, 2021
They are the best airlocks for carboys. Do not have to worry about filling them up with water or keeping an eye on them.
CJ B on Dec 12, 2020
Bulk aging
Ryan B on Nov 17, 2020
I no longer need to worry about carboy pressure with these.
Jeremy N on Nov 16, 2020
water in airlock never runs dry
Doug H on Nov 14, 2020
Heard about these on a youtube video - need something shorter than s-type for fermentation chamber
Alexandra O on Nov 4, 2020
GIULIO G on Nov 3, 2020
Super easy to keep clean
Shad S on Oct 24, 2020
Fool-proof, compared to airlocks that can run dry.
Doug H on Oct 11, 2020
I love these for long term aging
Zachary J on Oct 8, 2020
Recommended by fellow mead makers
Shad S on Sep 22, 2020
Could not find a #6 or #6.5
Elizabeth J on Sep 5, 2020
They work on big barrels
Luis H on Sep 3, 2020
I’m a bit tired of the old airlock
george j on Aug 29, 2020
No room in my fridge to use traditional bubblers (too tall)
Jesus Vanoye on Aug 24, 2020
Chris H on Aug 13, 2020
Heard they are good for wine storage
Mark D on Aug 7, 2020
Can always count u having what I need
James Armstead on Aug 6, 2020
Need them
Adam L on Aug 5, 2020
Post fermentation storage
Matthew S on Aug 5, 2020
i like the idea
Timothy M J on Aug 4, 2020
plug some carboys
Bob on Jul 22, 2020
i really want is because it is not rubber
christopher h on Jul 20, 2020
Smaller profile will help fit my carboys in my closets easier
Zachary J on Jun 16, 2020
word of mouth
Peter T on Jun 15, 2020
Shorter than a traditional bubbler airlock.
WILLARD D on Jun 3, 2020
to use in my carboy's and barrel. would like to smaller ones for 1 gallon carboy's
michael c on Jun 2, 2020
JP K on May 30, 2020
Roland B on May 28, 2020
Heard it was a better option than bubblers on some YouTube video
Bill D on May 28, 2020
Doin the most told me to get them
Timothy S on May 28, 2020
Just read about them and you have a decent price.
David Somers on May 27, 2020
Long aging in carboys
Charles S on May 23, 2020
Cold crashing and lagers
Peter B on May 22, 2020
ordered 2 to test replacing standard airlocks with the aterless ones for bulk aging
Conrad A W on May 20, 2020
Lucas A on May 19, 2020
I Like
La Forge Family V on May 12, 2020
Robin O on Apr 30, 2020
For long aging
Charles S on Apr 20, 2020
Works with the Speidel Orange Airlock
Dave E on Oct 10, 2021
Need it for my sampling carboy
Walter S on Sep 2, 2021
For those how have used both the bung and the hood- which do you prefer?
Ryza Wood on Jan 6, 2022
Silicone Stopper (Breathable) - Carboy
Silicone Stopper (Breathable) - Carboy
Premium Breathable Silicone Carboy Hood
Premium Breathable Silicone Carboy Hood
BEST ANSWER: If you are talking about plugging a five-gallon carboy, I strongly suggest you use the hood over the bung. I have used both. I have never had a single problem with one of the hoods. I use the bungs in my 1-gallon jugs from time to time, but I have experienced contaminated batches doing this. I can't say for sure the bung had anything to do with the contamination, but these have been the ONLY batches to ever become contaminated.
Doe this fit bubble big mouth opening in lid?
Shawn Wilson on Jun 28, 2020
BEST ANSWER: I prefer the breathable stopper than the 3 piece airlock as I no longer have to monitor the liquid level. Place it on top of a carboy or the Big Mouth lid and walk away until ready to bottle or keg.
Will this fit the one gallon glass jars?
Keith Smith on Sep 3, 2018
BEST ANSWER: They fit and seal well.
Like any other stopper, it needs to be dry when inserting -- dry inside the mouth of the carboy too with a clean paper towel.

4.8 / 5.0
38 Reviews
5 Stars
4 Stars
3 Stars
2 Stars
1 Star
Rated 5 out of 5
Works great, recommending to all my Wino n Hophead buddies
September 2, 2021
5 months ago
Rated 2 out of 5
they do not seal
These stay in the carboy as they should but they do not seal. They allow pressure to escape but they do not keep contaminates from entering. I used five of these and three of the mead batches were later found contaminated.
August 13, 2021
1 year ago
Rated 5 out of 5
Love these. Will never go back to a bubbler. New school way. No worries about drying out.
March 30, 2021
over 4 years ago
Rated 5 out of 5
Better than airlocks!
I love how I don’t need to use Starsan in an airlock anymore! This breathable stopper fits perfectly in my 6 gal carboy. It fits snug and never slides up. I recommend this product for all home brewers!
Bubblin’ away!
Bubblin’ away!
February 22, 2021
11 months ago
Rated 5 out of 5
Work great with glass carboys. They let air escape so don’t pop off!
January 19, 2021
1 year ago
Rated 5 out of 5
No longer have to worry about the liquid getting low in a 3 piece airlock
Sudden temperature changes would create a vacuum in the 3 piece that resulted in the sanitized liquid get low. I switched to the breathable stopper, and, now, I don't have to worry about keeping track of a liquid level.
November 11, 2020
over 2 years ago
Rated 5 out of 5
Love them!
Soooo much better than airlocks & such! Easier to clean, sanitize & maintain. A sensible alternative!
October 29, 2020
1 year ago
Rated 5 out of 5
I love these things..... I'll never go back to the bubblers.
October 22, 2020
1 year ago
Rated 5 out of 5
Much better than using a stopper and air lock, just make sure its not too wet or it will pop out if brew is degassing
September 26, 2020
1 year ago
Rated 5 out of 5
great item
I love this, although the pressure does tend to work it out of the neck of a glass gallon jug that I use for brew.
September 18, 2020
1 year ago