Features: brand new and high quality Setting the starting voltage: In the normal display voltage state, pressing the button will display the starting charging voltage; long press for 3 seconds, the digital tube will flash; you can start or stop the button to set the starting charging voltage value. Setting the shutdown voltage: In the normal display voltage state, pressing the button will display the charging voltage; long press the button for 3 seconds, the digital tube will flash; you can start or stop the button to set the charging voltage value. Factory reset: When the start/stop button is pressed in the power-on state, the digital tube will display 888; it means the factory reset setting. Application Fields: 12-24V storage battery. Input Voltage: for DC 10-30V. Display Precision: 0.1V. Control Precision: 0.1V. Voltage Tolerance: +/-0.1V. Specifications: Material:PCB Size:Approx.8.2x5.8x1.8cm/3.23x2.28x0.71in Net Weight:40g Note: Please allow 1mm errors due to manual measurement. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Package includes: 1x Charging Control Module