USB Fan Speed Regulator with Voltage Step-up and Buck Circuit

This electronic accessory is a USB fan speed regulator designed for small USB-powered devices, combining a compact control body with a simple rotary knob. As a voltage controller, it lets you adjust output smoothly and switch the power on or off, making it easy to fine-tune the performance of connected USB devices. It works with any USB power source and supports both USB-A and Type-C input, fitting common chargers, power banks, desktop ports, and laptops. The built-in voltage step-up and buck circuit allows flexible adjustment, and the small 46 x 21 x 18 mm body is neat on a desk or inside a DIY project. Use it to match air movement or power levels to the task at hand.