chletter – Class for typesetting letters to Swiss rules

The class en­ables com­po­si­tion of let­ters fit­ting into Swiss C5 & C6/5 windowed envelopes. No assumption is made about the language used.
The class is based on the standard LaTeX classes and is compatible with the LaTeX letter class. It is not limited to letters and may be used as a generic document class; it is used with the chex­tras pack­age.