Monitor and record power usage of home and work appliances for energy conservation and cost reduction analysis with the Extech PM120 Power Monitor. This helps you determine if the electrical device should be replaced with a higher efficiency unit. The PM120 has a large dual LCD. The primary display shows voltage, current, power, power factor, and frequency readings. The secondary display shows total time, cost (cost of operation per minute, day, or week), set, or energy. Design includes a standard, North American 3 prong plug, front socket connection, and backup battery that saves customized programs.