Residual current circuit breaker are dual safety protection devices integrating leakage current protection and overcurrent protection. They can accurately detect residual current in a circuit caused by electric shock or insulation damage, and quickly disconnect the circuit to prevent electric shock accidents. Simultaneously, they automatically trip in the event of a short circuit or overload, avoiding equipment damage and fire risks, thus building an efficient safety barrier for residential, commercial, and industrial power distribution systems. The products offer multiple leakage current protection sensitivity levels, including 30mA, 100mA, and 300mA, to adapt to the risk protection needs of different scenarios. They also support multi-pole configurations such as 1P+N and 2P, flexibly meeting the installation requirements of single-phase and three-phase systems. Developed and tested in strict accordance with the IEC/EN 61009 international standard, they ensure long-term stable operation in harsh environments, providing lasting assurance for electrical safety with reliable quality.