<http://schema.org/description>
"Most CNC machinists have already chosen a measurement system for their machine tools. When they find a workpiece dimensioned with a different system, they simply convert the print to their system of choice and run the job in that measurement system. However, there are some things to watch out for when switching measurement systems."^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.mmsonline.com/columns/imperial-versus-metric>