Features: Plug and Play, Only support for raspberry pie Pico, Monitor battery voltage (error 2%) and battery current (error 10%).Monitor charging current. If it is not in the charging mode, the LED will not be on, and it will wake up for 5 seconds every 2 minutes to reduce light pollution.In the charging mode, you can judge whether it is fully charged, and stop flashing after it is fully charged. In charging mode, the LED flashes when not fully charged.The ratio of each LED is equally distributed to prevent sudden load. The static consumption is less than 10mA. Serial output data.Only 18650 lithium battery is supportedSerial port output data format: The parameters are read from the onboard serial port. The USB To TTL cable can be connected to pins (TX and RX). The Silkmark is JP3.Note: It is normal to read the current consumption when PICO is not connected and the switch is turned on. After all, the board also consumes less , which can be ignored.Data format: [battery voltage mV] [charging current mA] [discharge current X10] mABattery voltage Charging current In Battery currentbe careful:When the data shows a negative sign, the battery is charging.When the data is displayed as positive, it indicates that the battery is in a state of consumption.Data parameters are separated by pipe symbols (the delimiter is ")MicroPython can use the split to split data information.Insert the battery (18650) into the slot.Material: ABScolour: BlackPackage Contents:1 x PICO UPS expansion boardOnly 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.