Silicone Stopper, 4 PCS Airlock Stopper, Carboy Airlock Stopper with 8mm Hole, Silicone Plugs for Homebrewing Beer/Kombucha (#6)

What I like about these silicone stoppers is that they fit the gallon jug. I had purchased "Amazon recommended " ones that claimed to be universal but they were too big for the carboy I was using. For reference, I am using one of these silicone bungs currently in a gallon glass carboy from Sprouts that had Apple juice in it. I had to fiddle with it a bit as it wanted to slowly slide up but a dry contact between the glass and silicone helped along with tightly wrapping plastic wrap to insure it would not move as pressure builds.It started bubbling within a couple hours of starting the mead. This silicone bung is constructed better than the hard plastic bungs that Amazon recommended.

Best stoppers. These are not the type of plastic that you can pick at with your fingernails. They fit into my one gallon carboy and airlock perfectly. If they slide out dry the stopper and charboy mouth.

Silicone is good but it didn’t like my carrots

I find these far better than the drilled rubber equivalent. 99% of the time they stay put after first install. Sanitize and dry with sterile towel, they stay in place.

Okay first off using in a 1 gallon jug, both need to be dry or it will slide out. The size is a bit small, I can stuff it almost flush in the top. It would be nice if when seated tight and snug (if there were slight carbonation won't back out) if there were 3/8's or 10mm left sticking out, to grip and remove it. Hence the 4 outta 5 Stars for design. Seller was fine. However these do plug the hole and do the job.

Perfect for homebrewing on 1 and 5 gallon glass carboys. Make sure it is dry before you try to use it though. Silicon doesnt stick well to glass when wet.

These stoppers have worked for my carboys! The flexibility of the silicone makes the insertion of the airlocks a little easier as well.

These airlock stoppers are a vast improvement over the rigid plastic stoppers that came with our carboys.