Instructions for use:1) Wide voltage (3V-5V) power supply. The chip is X9C103S; PCB board size: 2.7x1.3CM 2) 10K full-scale potentiometer. 3) The center tap of the potentiometer slides between 0-10k for a total of 100 stages (the typical impedance of the potentiometer sliding end is 40 ohms) 4) The digital potentiometer VL and VH ports correspond to the low and high end of the sliding rheostat, respectively, allowing the input voltage range from -5V to +5V. 5) The digital potentiometer module is accompanied by a test program. The program code is C language code and is written in sub-modules. The code includes: main function, display sub-function, button sub-function and header file of each module. You can use KEIL4 to open the source code for testing and learning. Colour:green Material:PC+Metal Package Contents: 8 x Digital Potentiometer Module Only 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.