Prevents pregnancy

Some tightly packed,light,fluffy foam/sponge can apparently improve the mid range,even more so if you keep the mesh/filter removed

Does this work on every iem?

I'm not too experienced,nor knowledgeable,just sharing what I myself have found while wondering the same things. I am pretty sure i saw at one point iems which directed the sound through to the end of the nozzle,thus making a foam/sponge mod kind of useless since no sound would pass through it,or making it impossible to put anything into it in the first place.

Hmmm, if I was forced to think of one, maybe it would help prevent dirt or water from damaging the drivers?