The 480400 Phase Sequence Tester has a rated voltage range of 40 to 600 volts and can test the phase orientation of 3-phase power sources at frequencies ranging from 15 to 400 Hz. The multiline graphical LCD displays phase orientation (clockwise or counter-clockwise) and whether each phase is active. No battery is required. Includes cable, three huge color-coded alligator clips, and a bag case.