ICM Controls ICM517 single phase surge protector with NEMA Type 3R rated enclosure. Suitable for use on a circuit capable of delivering not more than 10, 000 RMS symmetrical Amps, 240 Volts max, when protected by a circuit breaker rated 20 to 60 Amps maximum and 120 Volts minimum. made in United States. Manufactured by ICM Controls.