1The special arc extinguishing system and current limiting system can quickly disconnect the fault current of the DC power distribution system and ensure the reliable operation of the solar photovoltaic power generation system. 2High-performance flame retardant material with high temperature resistance, corrosion resistance and wear resistance. 3High quality internal copper parts, stable and reliable. 4Silver contacts, quick release response and sensitive action. 5Wiring terminal quenching treatment, environmental protection plating, with good torsion tolerance and anti-rust effect. 6High electrical life and mechanical life, mechanical life up to 20,000 times.