Features 【Usage 】This is a typical bistable circuit board, press trigger switch to energize relay and press again to dis-energize relay. 【Easy to Use】Designed with screw terminals, it is convenient to wire and easy to use. 【Features】Trigger switch connect to trigger signal, trigger signal is low lever effective. 【Use Suggest】If used for conditions of strong interface, it is suggested to connect a diode to input terminal in series, and connect a 470UF capacitor to GND in parallel. 【Notice】The power supply should be DC12V, but cannot be used for cars because instant voltage of cars may exceed 12V. Features: 【Usage 】This is a typical bistable circuit board, press trigger switch to energize relay and press again to dis-energize relay. 【Easy to Use】Designed with screw terminals, it is convenient to wire and easy to use. 【Features】Trigger switch connect to trigger signal, trigger signal is low lever effective. 【Use Suggest】If used for conditions of strong interface, it is suggested to connect a diode to input terminal in series, and connect a 470UF capacitor to GND in parallel. 【Notice】The power supply should be DC12V, but cannot be used for cars because instant voltage of cars may exceed 12V. Specifications: Power Supply: 12V DC Load Capacity: 10A, 250VAC; 10A, 30VDC Size: 1.5*3.5*4.5cm/0.59*1.38*1.77in Package Includes: 1 x Relay Module Package List