Features: With charging function, suitable battery ranging Supports 3.30v to 4.2V batteries (like 18650 or batteries), allowing flexible selection of suitable batteries. microed USB charging port Conveniently connection directly to a USB power supply for charging. Lightweight designing design makes it suitable for a wide ranging of portable devices and easy to integrate into projects. Boost function Boosts the input voltages to 5V, suitable for devices that require a higher voltages supply. Output current up to 1Ah meets the needs of most small electronic devices. Battery interfaced is PH2-2.0mm High efficiency TP5400 module with a high conversion efficiency, reducing energy loss and improving battery. The TP5400 boost module is extremely flexible and efficient power supply solution for a wide ranging of electronic projects. Specifications: Item: TP5400 Battery Shield Single Battery Charging & Boost Size: about 27.9x26.1mm/1.1x1.03in Supports 3.30v to 4.2V batteries (like 18650 or batteries) Charging Voltages Support:DC5-10V （Suggested 5V microed usb input） Boost Powering Support: 5v1a Charging Voltages Support 5V to 10V, Wide Compatibility Battery interfaced： PH2-2.0mm for wemos mini Battery Shield Package： 1Set/3Set Package Includes: 1PC Battery Charging & Boost Module note: Due to problem of lighting effect, there is certain tolerances in product, please understand. Please allow 0-1cm error due to measurement.