Square D QMJ363T is a panel-mounted fusible safety switch designed for providing reliable circuit protection and isolation in industrial three-phase power distribution systems. It features a 600V AC voltage rating and a 100A current rating, housed in a robust NEMA 1 enclosure with dimensions of 191 mm H x 112.78 mm W x 78.49 mm D and a weight of 25.311 lb. The switch is certified to CSA and UL standards and offers a high 200kA interrupting capacity at 480V for enhanced safety. Its typical applications include motor control centers, industrial machinery, and main feeder circuits where secure disconnection and overcurrent protection are critical.