Shakkan-Hou (Japanese ancient metrology)

<<< LENGTH >>>
1 Shaku = 30.30cm

 1 Sun = 0.1 Shaku = 3.030cm
 1 Bu = 0.1 Sun = 0.01 Shaku = 3.030mm

 1 Ken = 6 Shaku = 1.818m
(1 Jou = 10 Shaku = 3.030m)
 1 Chou = 60 Ken = 109.1m
 1 Ri = 36 Chou = 3.927km

< example >
 5 Shaku 7 Sun = 173 cm