They came as a set with two new Adam A3X speakers and first I did not unpack them as the speakers were quite OK without any foam underlay.
After a few days, I unpacked the foams and put them under the speakers, just to test and eager to "hear" some difference.
I couldn't hear any difference in the sound reproduction (as I'd expected), but now the speakers are acoustically separated from my desk. This makes a huge difference in the vibrations that the desk is picking up.
So in short, the audio I hear now, is ONLY coming from the speakers and no longer from the speakers and all stuff on my desk that was vibrating along...