SU203M-K4 is a 3-pole miniature circuit breaker designed for branch circuit protection in accordance with UL 489 and CSA 22.2 No. 5 standards. This device features a K-type trip curve with a rated current of 4 A and operates at voltages up to 277/Y480 VAC or 48/96 VDC. The SU200M series offers a 10 kA interrupt rating and supports accessories including auxiliary contacts, bell alarm, and shunt trip. This circuit breaker is suitable for industrial and commercial applications requiring reliable overcurrent protection with compatibility for busbar mounting systems.