Magic Flight Muad-Dib Flight Manual page 13

Begin to draw before engaging the battery and continue to draw until
there is no more visible vapor. The inability to capture all of the vapor
that is formed in one breath is a sure sign that you have overloaded your
screen.
While we recommend only using herbal concentrates that melt down
to a liquid, other types of concentrates can also be used. This can leave
small amounts of ash in the screen which can be gently swept clean with
the provided brush.
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