5Pcs Mini USB Fan Governor Wind Speed Controller Air Volume Regulator Cooling Mute Multi Function Fa Efficient Speed Regulation: Easily control the wind speed of your USB fan with this versatile speed controller. Suitable for 5 pieces, it allows precise adjustment to meet your cooling needs. Quiet Operation: Designed with a mute function, this regulator ensures a noise-free environment, perfect for work or sleep. Multi-Function Design: More than just a speed adjuster, this device also acts as an air volume regulator, enhancing the functionality of portable fans. Compact and Portable: Its mini size makes it easy to carry and use anywhere, powered conveniently by DC 5V. Due to different batches, there may be differences in product appearance, color, and printed text, which not affect the use. Color:As Shown Material:PCB Package Contents: 5 * Mini USB Fan Governor 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.