You can check the battery level. You can charge up to 3 batteries, with charging prioritized from high to low battery level. Batteries with higher charge are charged first. Supports PD and QC3.0 fast charging. The MINI 3 battery can be used as a power bank to charge the remote control or other USB devices. It also provides storage for batteries, allowing for easy portability. Input: 5V/9V/12V3A (max) Output: 8.5V4.0A (max) USB output: 5V/2A Charging time (with input: PD 40W or higher): 2453mAh battery: approximately 90 minutes (45 minutes per battery) 3850mAh battery: approximately 130 minutes (65 minutes per battery) Color: As shown Material: Plastic Package Contents: 1 x 3-Way Butler 1 x USB-A to USB-C Charging Cable 1 x USB-C to USB-C Charging Cable Note: The package includes only the items listed above. Other products are not included. Note: Lighting effects and different display screens may cause slight variations in color between the product image and the actual item. Measurement may vary by +/- 1-3 cm.