KISSsoft recognises two unit systems: metric and imperial (US Customary Units). If the value in line UNITS in section [SETUP] of the KISS.ini-file is 0 then KISSsoft uses the metric system, while 1 will indicate that the imperial system should be used.
Using Extras ⇒ System of Units the unit system can be toggled. This setting will be recorded in your personal Registry (see 7.2), but not in the KISSini (see 7.1).