You can find distribution boxes made from various distribution box materials such as steel, aluminum, PVC, polycarbonate, high-density polyethylene, and thermoset plastics like SMC. Each distribution box material has its own special strengths. A feeder usually begins with a feeder breaker at the distribution substation. At this. A distribution box, also known as a power distribution box or electrical distribution box, is used to distribute electrical power safely to multiple circuits. These boxes have inner and outer doors, powder-coated exteriors, and are designed for safety and aesthetic appeal, with rainproof tops for outdoor work.