This is a dual-channel latching relay，it can keep the original state from changing in the event of a power failure. If you need to change the state, only need to rise or falling edge. Since the power supply can be cut off without changing the operating state,so that the module is specifically designed for low power consumption circuit design.It is widely used in remote control, telemetry, communication, automatic control, electromechanical integration and power electronic equipment, is one of the most important control components