Home distribution boxes typically handle single-phase power supplies and contain 6 to 24 circuits. They include standard circuit breakers for lighting, outlets, and major appliances like water heaters and air conditioning units. A distribution board (also known as panelboard, circuit breaker panel, breaker panel, circuit breaker, electric panel, fuse box or DB box) is a component of an electricity supply system that divides an electrical power feed into subsidiary circuits while providing a protective fuse or circuit. A distribution board or distribution panel (DP) is an important part of an electricity supply system. It provides information on how these components are interconnected and how the electrical power is distributed throughout the building.