This black/white locking connector from Hubbell Wiring Device-Kellems is a great choice to prevent accidental power interruptions. This locking connector has a Non-NEMA configuration with a voltage of 480VAC and an amperage of 50. It has 3 poles and 4 wires. It has 3 phases. This has a grade of industrial/commercial. It is made of super tough nylon material. Standards include: UL/CSA.