Speck Electronics Xtramix - Manual (Page 18)

The front and rear panels are a high quality painted surface and the panel
lettering is applied using a silkscreen printing technique.
To clean the front or rear panel, wipe the surface gently using a soft lint-
free cloth to avoid scratching the panel or markings. Paper towels are
not recommended. Commercially available window cleaner solutions
may be used; however, the solution should be applied to the cloth and
not the panel to avoid the seepage of liquid to the inside of the
enclosure.
Cleaning
IMPORTANT!
DO NOT USE BRUSHES OR FEATHER DUSTERS TO REMOVE
DUST. THIS MAY CAUSE DUST TO FALL INTO THE OPENINGS
AROUND THE PUSHBUTTON SWITCHES.
13 Chapter 3 Installation Section