Square D™-brand I-Line™ circuit breaker power distribution panelboards are for use on AC or DC systems. The panels, labeled cULus (compliance to UL and CSA standards certified by UL) are also Underwriters Laboratories® (UL®) Listed under File E33139. Service entrance panelboards meeting the requirements of CSA are available in Canada factory-assembled only. I-Line circuit breaker panelboards are available as 400–1200A main lugs only and 100–1200A main circuit breakers. This I-Line Panelboard is 4.5 in (H), blank extension, has a quantity of 5 ea per box.