Item Type: Voltage Reference Module Material: PCB Board+Acrylic Model: AD584 Color: Yellow Measuring Range: 2.5V, 5V, 7.5V, 10V Power Supply: Polymer 503035 500mAh x 1 (Built-In Battery) How to Use: Get the product, turn on the power button, the indicator shows which range, the module test is in which range. Press the middle button of the module again to switch the range. The user can take the test line and insert it into the positive and negative holes for measurement. 1Built?in AD584 module, with the highest accuracy and stability, reliable to use. 2The same port can output a reference voltage of 2.5V / 5V / 7.5V / 10V. 3MCU switch 4?channel reference voltage output, with LED indicator, single?key operation. 4Voltage reference module, with stable performance, easy to install and use. 5Using high?quality PCB board + acrylic material, durable and long?lasting.1 x Voltage Reference Module