A novel test lead can be used to connect an aging line with a voltage or multi-meter in order to monitor the voltage output by the aging line. The aging line is used to age electronic devices and components, particularly cathode ray tubes, during the manufacturing process. The test lead includes a plug adapted for ready connection to an output socket of the aging line without requiring any disassembly of the socket. The other end of the test lead preferably includes a number of clips, banana or alligator, for connecting the lead to the voltage or multi-meter. In this way, the output voltage of the aging line can be easily and rapidly tested for conformance with predetermined specifications.