Hush Bubbles

What's the difference between a bubble box and a silent bubble? 3

I was looking for fishing equipment and I found some aerators. One is called a bubble box and the other is called a silent bubble. The two are almost identical, but I can't tell the difference between them. Thank you very much.

The difference is in the amount of internal components and pumped air, as well as the silence on each run.

Hush Bubbles