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 Regalia Kleinodien ("Aachen jewels"). It is not known how long they have been considered among the Imperial Regalia, nor how long they had been in Aachen. The inventory of the regalia during the late Middle Ages normally consisted only of five to six items. Goffredo da Viterbo counted following items: the Imperial Cross, the Holy Lance, the crown, the sceptre, the orb, and the sword. On other lists, however, the sword is not mentioned. Whether the medieval chronicles really do refer to the same regalia which are kept in Vienna today depends on a variety of factors. Descriptions of the emperors