The foam filter I'm talking about is in the eartips, the IEM itself still has a grille and internal filter like this. There are many IEM's with more open ports if you're concerned about wax or debris getting in the IEM itself. You can take the foam out of the stock eartips though and put it in other ones but I don't know how well it would stay in. The Senn IE Pro eartips have foam filters in as well but don't have paper-thin silicone like the IE300/600/900 stock eartips (I think IE200 as well).