The Metrahit Im Xtra is a portable and rugged multimeter designed for use in the field. It is suitable for safety testing and diagnostics at electric machines and includes the measuring functions of a TRMS digital multimeter, an insulation resistance measuring device, a milliohm meter using four-wire connection measuring technology and a coil tester. Therefore, the unit is as easy to use in aircraft cockpits as in other confined measuring spaces, where several individual devices are employed otherwise.