Imperial units commonly used units for length are (li), (tseung/cheung), (tsek/chek), (tsun/chun), (fen/fan) in descending scale order. These units are now rarely used in daily life, the imperial and metric systems being preferred. The imperial equivalents are written with the same basic Chinese characters as the Chinese system. In order to distinguish between the units of the two systems, the units can be prefixed with "Ying" () for the Imperial system and "Wa" () for the Chinese system. In writing, derived characters are often used, with an additional (mouth) radical to the left of the original Chinese character, for writing imperial units.
Imperial Estate century to as many as 45. It is likely that this system was first introduced under Emperor Sigismund, who is assumed to have commissioned the frescoes in Frankfurt city hall in 1414. As has been noted from an early time, this representation of the "imperial constitution" does not in fact represent the actual constitution of the Holy Roman Empire, as some imperial cities appear as "villages" or even "peasants". E.g. the four "peasants" are Cologne, Constance, Regensburg and Salzburg. The Burggrave of Stromburg (or Straburg, Strandeck, and variants) was an unknown entity even at the time. The representation of imperial