Extech um200 high resolution micro ohm meter extech um200 the extech um200 digital high resolution micro ohmmeter is a precision meter that provides resolution down to 1 956 omega using 4 wire kelvin clip test leads its built in comparator enables hi lo resistance testing with 20 sets of prestored values the meter is sufficiently sensitive to perform cable length measurement feet or meters supplied with 4 wire cables with kelvin clip connectors rechargeable li polymer battery ac ada