Therefore, the thickness of the sheet metal of the cabinet body of the power electrical distribution box is usually not less than 1. 0mm or thicker, may be. Distribution boxes are also known as the “commander” of household circuits, with primary duties of power distribution and security protection. But when faced with a variety of materials and complex functions of distribution boxes in the market, the majority of customers tend to be bewildered. The box capacity table shown (page A-5) is reproduced in part from the NEC® as a quick reference and. trial applications. Different incoming devices are available withi d outgoing devices. Think of them as traffic controllers for power—they direct energy where it needs to go while protecting against overloads or. Plastic Electrical Box, also known as a consumer control unit or electricity control unit. JUNON new range: C6 series Single Phase.