The Extech 480403 Motor Rotation and 3-Phase Tester has a 40 Volt to 600 Volt rated range for testing phase orientation of 3-phase power sources over a 2 Hz to 400 Hz frequency range. LEDs indicate phase orientation (clockwise or counter-clockwise) and whether each of the phases is live. In addition, it indicates rotation direction of the motor to ensure that it doesn't get damaged from incorrect wiring. Meter comes complete with cable and three large color coded alligator clips, pouch case, and 9V battery.