Fangrui Product Details Precautions: 1. Ac Power Cannot Be Input, Let Alone 220v Mains Power. 2. The Maximum Allowed Input Voltage Is 75v, And No Overvoltage Input Or Reverse Polarity Connection Is Allowed. 3. The Output Cannot Be Completely To Prevent Backflow. When Connecting The Battery, Ensure That The Output Voltage Of The Power Module Is Higher Than The Battery Voltage, Or Connect A Diode In Series With The Positive Terminal Of The Output To Prevent One-way Conduction. Prevent Battery Voltage From Flowing Back And Burning The Power Supply. 4. When Connecting The Output Terminal To The Battery, Be Careful Not To Reverse The Positive And Negative Poles. 5. The Product Is A Step-down Module, The Maximum Output Voltage = Input Voltage * 0.95-1v. Protection Mechanism: Input Undervoltage Protection (lup): 5.5-64v Adjustable, Factory Default Value 5.5v Output Overvoltage Protection (oup): 1-66v Adjustable, Factory Default Value 66v Output Overcurrent Protection (ocp): 0.001-23a Adjustable, Factory Default Valu