1. The shell frame has a high 1P+N double breakpoint (18 modulus 40A) and a high breaking capacity (6kA). 2. lt has contact position indicating window, and has higher security. 3. Current-limiting contact system, magnetic blown arc extinguishing device, avoid products and equipment to withstand large short-circuit current, improve product arc extinguishing Ability to ensure the improvement of breaking capacity. 4. The shell and function keys are made of imported PA nylon with high flame retardant, high temperature resistance and impact resistance. 5. lts shape is novel, its structure is reasonable, and it has many patent protection. 6. The product not only has overload, short circuit, leakage protection function.