This is a connection accessory for I-Line Panelboards. This is a plug-on subfeed lug kit for I-Line panelboards for PowerPact L-Frame, LA-LH circuit breakers. This has a amperage rating of 400 amps. The frame size 400 amp. The lug accepts (1) #1-600 kcmil, (2) #1-250 kcmil, Al/Cu. This product complies with UL standards.