A distribution box divides one incoming electrical supply into multiple outgoing circuits. Typical components include a main switch, busbars, circuit breakers, neutral and earth bars, terminals and an enclosure. Today, electrical systems are essential for homes and industries. What is Electrical. For procurement professionals, electrical contractors, and project managers, choosing the right Distribution Box (DB Box) is a critical decision that directly impacts system safety, reliability, and long-term operating costs. Distribution Transformer The distribution transformer is a main and largest equipment of distribution substation.