These work great with the Speidel airlocks!

These work great with the Speidel airlocks!

Exactly what I was looking for. Quick delivery.

Exactly what I was looking for. Quick delivery.

Good idea to keep a spare stopper on hand.

Good idea to keep a spare stopper on hand.

Just like the original - it's a perfect fit. Fits much better than the stoppers fit into glass carboys (this one never pops back out)

Just like the original - it's a perfect fit. Fits much better than the stoppers fit into glass carboys (this one never pops back out)

This is just for the red stopper, not the entire stopper/airlock combo. Nice quality

This is just for the red stopper not the entire stopper/airlock combo. Nice quality

This rubber bung fits perfectly in the 2L Erlenmeyer flask found in the yeast starter kit. I use the Speidel fermentors, so using the same airlock for the yeast starter is just one less thing I have to worry about.

This rubber bung fits perfectly in the 2L Erlenmeyer flask found in the yeast starter kit. I use the Speidel fermentors so using the same airlock for the yeast starter is just one less thing I have to worry about.

I personally dislike airlocks like this, too many moving parts. No harm in the classic S-shape.

I personally dislike airlocks like this too many moving parts. No harm in the classic S-shape.