The RPM21F7 is a plug-in power relay from the Harmony RPM series designed for switching electrical circuits. It features two changeover (2 C/O) contacts with a conventional enclosed thermal current rating of 15 A and operates on a 120V AC control circuit. This power relay offers a maximum switching capacity of 3750 VA, a mechanical durability of 10 million cycles, and includes a lockable test button for easy diagnostics. The relay is designed to operate in ambient temperatures ranging from -40°C to 55°C, making it suitable for various industrial power switching applications.