Niles OS6 Installation & Operation Manual page 15

If you are using an applicator or brush and a can of paint, thin the paint first.
Thick paint will tend to clog the grille holes.
REPLACING THE GRILLE
Carefully fit the grille into its recess so that it is barely in place. Starting with
one corner, go around the speaker, pushing the grille in a little bit each time.
You should be gentle, the aluminum grille can be easily bent out of shape. You
will feel a positive "snap" when it is fully in place.
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