Feature 1.100% new and high quality 2.Suitable for Mouse roller 2Pcs Original TTC Mouse Encoder Highly Accurate 5MM 5.5MM 7MM 8MM 9MM 10MM 11MM 12MM 13MM Green Core. When scrolling the web page, it will often jump up and down Solve the roller wheel problem. The encoder can be commonly used as long as the encoder of your mouse have the same height with it. The new TTC green core is moderate in strength, high precision, accurate positioning, very comfortable feel, and suitable for office games. With a life span of 5 million times, it has reached the Japanese standard. Currently, it is the leading domestic player, far exceeding the market's lifespan of black core and common green core. 1.materialmetal 2.colorAs the pictures shown 3.sizeas the picture shows Package include:2pcs Note: Please allow minor error due to manual measurement. The colors may be a little difference for the different monitor display.