EC3GB series ground bars are intended for use in Siemens ES and PL series of load centers with a box height of 24, 27, 29, 30, 35, 36, 38, or 42 inches. For the ES and PL lines of load centers this would include 125A load centers of 24 1-Inch spaces or more, 150A and 200A load centers of 20 1-Inch spaces or more, and all 225A load centers. The ground bars can be mounted in one of 4 locations inside the load center: top right, top left, bottom right, and bottom left. Up to 4 ground bars can be added to each load center.