It is a 28-port full Gigabit Layer 2 unmanaged rackmount industrial Ethernet switch designed and developed for industrial communication network applications. The switch is equipped with 4 Gigabit Combo optical multiplexing interfaces and 24 Gigabit electrical ports, which provides flexible networking methods. Among them, the Gigabit Combo Optical Multiplexing interfaces can be arbitrarily configured as Gigabit optical or Gigabit electrical ports to meet the needs of different scenarios.