How does bottle trap work to prevent stink?

Do you know how bottle trap works to prevent the stink?

Pls see the above picture, it explains how it works.

The seal height is 60mm for this bottle trap and it will store the waste water with height 60mm. Then the stink will not go through this water storage area, so you can not smell it when washing the face.

That means seal height is very important when you choose the bottle traps.

Usually, it is better to choose the one with seal height more than 60mm.