Mounts a single KD3400 Breaker in a PRL4 Power Line Cutler Hammer Panelboard. This kit is capable of mounting one breaker across the panel. Kits include copper conductors, end brackets, cover plates and screws to fasten. Most panel have a single row of tapped and drilled holes. another unique feature of the kit is that the conductors themselves are round in the middle and flatten out at both ends to connect to breaker and bus.