7_ (Read "Seven underscore" - A number 7 and a set underscore) is one of the main signs used by Atelier Hans Zirngast to sign its (especially design activities related) productions. One meaning: Atelier Hans Zirngast is "unterbewertet". It is "under score".
Put visually like a logo the underscore is set below the number 7.
In digitally set type characters (like here on this page) the underscore is often used to the right side following the number 7.
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