Provides a visual confirmation of the best possible onsite ground...the ground of your facility's electrical system. Just insert the Model 61-038 into a 3-prong, 120V receptacle. The device diagnoses the 3-wire circuitry and indicates any possible common wiring faults. If none exist, you are assured of a "proven" means to drain static charges. Bright, long-life, neon lamp indicators have wrap-around lens covers to provide visibility from all angles. Accepts any ground cord with standard banana plug connector.