Square D™ QO™ Value Pack 200-Amp 42-Space 42-Circuit Indoor Convertible Main Breaker Qwik-Grip Load Center for Plug-on Neutral breakers includes the cover and a selection of breakers. It is UL listed for residential, commercial, and industrial power distribution. This load center is built with a shielded copper bus bar that is plated for reliability. QO load centers are tested and listed only for QO circuit breakers. QO load centers are the world's finest designed with industry-leading features for flexible application. QO load centers include features engineered for fast installation and wire savings.