Just like the speaker grills you see in cars and home audio equipment, these work as both a filter and a grill. Comes in many pleasing colors.

05-19-2008
Reviewer: MINDSCI (15)
It is much more flush than the photo indicates. It mounts between your fan and case panel. Holes are a little too big for the best filtering, so I glued some fine mesh black patio screen to the back of it.