Industrial-grade locking plug designed for heavy-duty electrical applications. This 4-pole, 5-wire grounding plug is rated for 30 Amps and 120/208V 3-Phase Y (3ØY) configurations. It features a rugged black ribbed nylon body for enhanced grip and durability, with clear markings for voltage and amperage on the face. Part number 231A is visible, indicating a high-quality component suitable for commercial or industrial power distribution setups. The twist-lock mechanism ensures a secure connection to prevent accidental disconnection in high-traffic or vibrating environments.