Type QO load center with cover and main breaker installed. Plug-on Neutral ready and built with a shielded, copper bus bar that is plated for reliability. 100 amp main breaker included. Ideal for residential, commercial, and industrial power distribution. Engineered for fast installation and wire savings. UL (Underwriter's Laboratories) listed for residential, commercial, and industrial power distribution. This load center allows up to 34 total circuits.