Description: Built -in AD584, highest accuracy and stability Same port can output reference voltage : 2.5v, 7.5v, 5v, 10v The MCU switch 4-way reference voltage output with LED indicators Single - button operation switch reference voltage 4mm banana socket as output interface Note: Please check input battery charging voltage and do not charge with more than 5.5 volts Please charge with a USB adapter. Package includes: 1 x High Precision Voltage Reference Module with housing