Fermentation TPE Rubber Stoppers – Drilled Bungs for Airlocks (#7 Drilled Stopper, 4-Pack)

these fit my big carboys and the hole is perfect for my tubing i use for the bubblers

Work perfectly in my 6.5 gallon carboys

I have a 1 gallon carboy that i bought these for, one size smaller would have been better. I got these guys to fit but with a bit of a struggle.

Right size for a 5 gallon carboy to seal it off when doing my home brew

Just what I needed for my wall fountains.

I used these to make glug glug water top offs for my hydroponic garden. A 1/2” tube fit tightly in the center hole and the #7 was the perfect fit in the glass 5 gallon jug. Sealed very well.

2 L does not hold 2 L of volume, I had hoped the tank itself was 2 Liters.

These work much better in the neck of carboy than solid ones. We ended up drilling a couple of these to accomodate the airlocks