Industrial encoder accessories, encoder wheels, and encoder meter wheels are all components used in conjunction with encoders to help measure the position, speed, or direction of a rotating shaft or linear motion. Encoder wheels are typically made of Aluminum and Polyurethane have evenly spaced slots or holes around their circumference. As the wheel rotates, an optical or magnetic sensor detects changes in the pattern of slots or holes and uses this information to calculate the shaft's rotation angle or linear travel distance. Encoder meter wheels are similar to encoder wheels, but they have a tire or tread that makes contact with the surface being measured. This type of encoder is commonly used for measuring conveyor belt speed or other linear movements. [Material] Made of Aluminum and Polyurethane, not easy to wear, durable and lasting performance. It's a great substitute for your product. Colour:As Shown Material:Aluminum and Polyurethane Size: thickness:15mm or 0.59 inch Diameter:100mm or 3.94 inch Bore Diameter:8mm or 0.31inch Package Contents: 1 x Encoder Wheel 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. Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.