An enclosure has one or more panels produced by extruding and cut to desired length. An extruded panel of the enclosure may integrate heat sinks, threaded rod locations, and internal grooves to attach adjacent panels. Top and bottom plates may be joined to the panels by threaded rods passing from the top plate through to the bottom plate via the threaded rod locations engineered into the extrusion, enabling the panels and plates to be pulled together by turning the threaded rods. Once assembled, the enclosure may accommodate a variety of electrical equipment at time of assembly and/or at the enclosure installation site. The enclosure has applicability in electrical power distribution, for example as a combiner box in a solar power distribution system.