The FUJI ELECTRIC BW9RHA-1 is a field-installable undervoltage trip coil designed for seamless integration with Fuji Electric's BW400, BW630, and BW800 series molded case circuit breakers (MCCBs). Featuring a 120-130 VAC sensing range and left-side mounting, this accessory enhances circuit protection by ensuring automatic disconnection during undervoltage conditions. Its 19.69-inch 20AWG lead wires facilitate easy installation, making it an essential component for maintaining operational safety and reliability in industrial automation systems.