Purpose: Battery charging control protection switch Set the starting voltage: in the normal display voltage state, pressing this button will display the starting charging voltage; long press the 3s digital tube will flash; you can set the starting charging voltage value by starting or stopping the button Set the stop voltage: in the normal display voltage state, press this button to display the stop charging voltage; press and hold the button for 3 seconds, the digital tube will flash; you can start or stop the button to set the stop charging voltage value Input voltage: DC 10-30V Output type: direct output Application field: 12-24V battery Material:PC+metal colour:Blue Package Contents: 2 x Charge Control Module Battery Protection Board Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.