The ZM-104A from TOA is a portable impedance meter that can measure the impedance of speaker lines up to 100 k ohms. It has an adjustable zero for accuracy on all ranges. It runs on four "AA" batteries and has an easy-to-read meter that calibrates directly in ohms. It includes a carrying case, test leads, and impedance-to-power reference chart.

• Portable impedance meter that can measure the impedance of speaker lines up to 100 k ohms