Felt washers on around control shafts.

[Ed in Tx]

Originally Posted by old_coot88

Possibly to keep the knob from marring the finish and to prevent a visual gap.

yep.
Used a lot for hiding the bright metal washer & nut on the threaded control shaft you may otherwise see in the gap between the knob and panel opening.

[Notimetolooz]

OK. That seems like that answers that one. I didn't think the felt would work to well to keep the dust out, since the cabinet is ventilated anyway.