Convert from shaftment [ancient] to centimeter

Unit Definition (shaftment [ancient])
A shaftment, when used as a unit of length, is usually six inches or two palms, i.e. 15.24 cm (for the international inch). It is thought to be the distance from the tip of the outstretched thumb to the other side of the palm.In English this unit has mostly fallen out of use, as do others based on the human arm: digit (1/8 shaftment), finger (7/48 shaftment), palm (½ shaftment) hand (2/3 shaftment), span (1½ shaftments), cubit (3 shaftments) and ell (7½ shaftments).

Unit Definition (centimeter)
The centimeter (or centimetre) was the basic unit of distance in the former CGS (centimeter, gram, second) version of the metric system, equal to 0.01 meter. The engineering standard uses every third power of ten, such as 10e3, 10e9, 10e12, etc., and for small numbers 10e-3, 10e-6, etc. The only exception is the centimeter. "Cent" means a hundredth, or 10e-2, but the centimeter is still commonly used because it is such a convenient unit for measuring length.