KYN28A-12 (GZS1) type indoor metal armored pull-out switchgear is a complete set of power distribution device for 3-10kV three-phase AC 50Hz single bus and single bus segment system. The main power plant, small and medium-sized generator power supply, industrial and mining enterprises and utilities distribution and power system of the secondary substation, power supply and large high-voltage motor starting. For the purpose of control protection and detection. The switchgear can meet the requirements of DL/T404, IEC60298, GB3906 and other standards. It has the interlocking function of preventing push and pull circuit breaker with load, preventing misopening and closing circuit breaker, preventing the grounding switch from closing and breaking when the grounding switch is in the closed position, preventing strapping into the charged compartment and preventing misopening and closing the grounding switch when the grounding switch is in the closed position. It can be equipped with VS1 vacuum circuit breaker. ABB VD4 vacuum circuit breaker can also be used. It is a power distribution device with superior performance.