CDB2 series circui breakers have the advantages of small appearance, light weight, excellent and reliable functions, higher breaking capacity, rapid tripping and long life. As for case and parts, they adopt high resistance and impact resistance plastics. They are mainly applied to the AC 50Hz/60Hz circuit with rated operation voltage 400V or less provide circuits with overload and short-circuit protections, and to make and break the electrical device and lighting circuit infrequently. The product can be installed with undervoltage release and Shunt release, and also can be used for separating, and protecting the undervoltage of the circuit and breaking the long distance.