QO Circuit Breaker Load Centers, QOSAMK, from Square D are Underwriters Laboratories (UL) Listed and CSA rated panelboards. They are designed to meet residential, commercial, and industrial requirements to protect electrical systems, equipment, and people. NQ and NF Panelboards are convertible from main lug to main breaker. This enclosure drip hood is rated as a type 2 with drip shield cover The width for this box is 20 in. NQ and NF Panelboard interiors are field convertible to top or bottom feed. NQ and NF Panelboards are suitable for use as service equipment. Panelboard enclosure box is UL listed and CSA certified by UL.