It is recommended to use Hall Joystick structure with a lifespan of more than 3 million. Sensor Module lifespan is approximately 10 million. If your joystick structure is damaged, after replacing the structure, the two Hall Joystick Sensor Modules do not need to be removed and can continue to be used. It is advised to purchase the upper and lower arm modules together. Installing the joystick with only one module may lead to incompatibility or other issues. Due to different production batches, there may be variations in product appearance, color, and printed text, which will not affect functionality. Type: Upper arm. Color: Green. Material: Plastic. Package Contents: 40 x Sensor Module. The package includes only the items listed above; other products are not included. Note: Lighting effects and monitor differences may cause slight color variations between the image and the actual item. Measurement error allowance is +/- 1-3 cm.