Supports MPPT (Maximum Power Point Tracking) function, maximizing the efficiency of the solar panel. On-board MPPT SET switch, select the level closed to input level to improve charging efficiency. Supports solar panel / power adapter/USB multiple methods of connections for charging Suitable for 5V-24V solar panel, with MPPT, DC-044 Power Jack and KF128L-2P Terminal Block On-board 18650 holder and PH-2P socket, convenient to connect multi kinds of 3.7V rechargeable battery or pack Onboard various status indicators for checking the status of solar panel and battery easily. Multi protection circuits: over charge / over discharge / reverse protection / over current, stable and safe to use. Note: The battery is NOT included.