This device is a USB fan air volume regulator that sits between a 5.0V USB power source and a USB fan, enabling twospeed operation without software. Compatibility: Suitable for the very common 5.0V USB fans. Function and features: USB fan air volume regulator for easy speed control. Twospeed operation: Speed 1: nonadjustable, direct 5V supply to the fan motor. Speed 2: internal circuit board boosts the USB 5V before feeding the motor, increasing airflow. Plugandplay design with no software required. Connection method: Insert the governor's male USB plug into a USB port on a computer, charger, or other USB power source. Plug the fan's USB plug into the governor's female USB port. Alternatively, power the setup from a USB 5V power supply. Practical notes: The device acts as an inline regulator between the USB power source and the fan to adjust airflow. The higher airflow is achieved only when using the second speed with the internal board. Use scenarios: Desktop or laptop cooling: reduce fan noise by selecting the first speed while maintaining adequate airflow. Compact USBpowered cooling for small form factor systems or SBCs (such as a Raspberry Pi), where adjustable airflow helps manage temperature without software. USBpowered cooling in a portable setup or USBpowered enclosure where a simple, hardwarebased speed adjustment is desirable. Availability of details: Size and material are not specified by the provided information. Function, compatibility, and performance are as described.