Convert from fist to micrometer

Unit Definition (fist)
The fist is an informal unit of distance equal approximately to the hand (10 centimeters or 4 inches). The unit represents the width of a clenched fist.

Unit Definition (micrometer)
The metre, symbol: m, is the basic unit of distance (or of "length", in the parlance of the physical sciences) in the International System of Units. The internationally-accepted spelling of the unit in English is "metre", although the American English spelling meter is a common variant. However, both American and non-American forms of English agree that the spelling "meter" should be used as a suffix in the names of measuring devices such as chronometers and micrometers.