Any battery with a voltage ranging from 6V to 30V can be used normally. The alarm voltage can be adjusted by pressing and holding the button. It can also be freely adjusted within the range of 6V to 30V. Once the real-time voltage of the input battery is lower than the set alarm voltage, the buzzer of this device start to alarm, and all outputs be automatically cut off after 2 minutes. (After the output is cut off, the battery consume almost no power.) It can effectively protect our lithium battery from over-discharging during the discharging process!!! If you find the buzzer noisy when it is ringing, you can mute it by briefly pressing the button. However, the automatic power-off after 2 minutes still be executed as normal. Regarding the fast charging module part: It uses the 3518 fast charging module. Since it is a step-down module, the 20V gear of the Type-C port can only be activated when the input voltage is 21V. The maximum broadcast power can reach 100W. It is okay to use 100W for emergency situations in a short period. For long-term use, it is recommended to use a power of 65W or below. When charging at a high power, the fast charging module generate a lot of heat. Please use high-power charging in a well-ventilated environment or use an external fan to enhance heat dissipation. There are openings on both the upper and lower sides of the module to enhance heat dissipation. When charging and discharging the lithium battery, it is best to be nearby so that you can deal with any potential risks in a timely manner. Project Name:Automatic Alarm Power PD Integrated Module Input voltage:6-30V Power:65W MAX Interface: Support PD3.0/QC3.0 Color:C: & Green Material:ABS Package Contents: 1 * FPV automatic power-off module 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.