Regular standard universal stopper. Always a classic all around winner. Has its flaws as usual. But an always needed staple.

So far so good. These fit all my carboys of different manufacturers. Easy upgrade to replace my old rubber stoppers that looked nasty. No problems making good seals.

These work great with an airlock on 5 gallon carboys.

I got these by mistake... and an awesome mistake it was. Since they have that hallow inside it allows the cork to get deeper n the neck and hold better

I have carboys of several different sizes and styles. This stopper allows me to use them efficiently. Pretty handy I would say.

I should have read the listing better this won?t fit plastic carboys. I?ve found another use for it though. It is well made and I think I like this style of bung better than the solid ones.

A good stopper. fits in 64oz and 128oz store bought cider jugs. Felt a little unsure about the seal after multiple times of putting in the airlock. Poured a little sanitizer into the top and no bubbles so I feel that it will seal after multiple reseatings of the airlock. Seems to be a harder material that will withstand the oxidative stress of sanitizer unlike other stoppers and caps that dry and crack.

I have several 5 gallon glass carboys and these stoppers have worked perfectly in them every time. However I've had a lot of trouble using them with a 6 gallon glass carboy as the neck is narrower and the stopper hates to slide down and stay in place (wet or dry). 'Sokay I never liked using that carboy much anyway and mostly now only use plastic bucket primary and 5 gallon glass secondary. This is a great stopper in my world!

I like these stoppers. As others have pointed out they need to be dry to fit well but otherwise they are much better than the traditional stoppers that behave much worse in terms of staying in the carboy. Unless you go with a carboy cap these are the stoppers to use.

I like the "universal-ness" of this product. However when I first do a batch and the neck of the carboy is still wet from sanitizer these have a tendency to push out and just barely rests on the top of the carboy. I have to use a rubber band to secure it in the beginning.

I almost exclusively use these over the traditional stoppers. These fit a larger variety of sizes and won't get stuck or accidentally pushed through into your carboy. I only wish they made a smaller size that would work with a 6 or 6-1/2 bung hole.

Easier to grip for removal and does not pop out when wet. Great!

Fits great and easy to use. Better than the solid ones that seem to slip in and out