USB Fan Governor model ZK-UFS delivers precise, stepless speed control and timed shutdown for USB-powered fans, with soft start to protect motors and a compact footprint for easy installation. Key benefits - Precise, quiet airflow control: Stepless governor lets you set fan speed anywhere between low and high to balance cooling and noise. - Protects fans and power source: Soft start reduces startup current stress and prevents sudden surges. - Save power and avoid running fans unnecessarily: Built-in timer and sleep mode allow automatic shutdown after a set period. - Easy to use and install: Small inline unit connects between a USB power source and the fan with clear controls and a display. - Wide compatibility: Works with USB power sources from DC 4 V to 12 V and regulates fan voltage from DC 2.5 V to 8.0 V. What makes it stand out - Smooth stepless adjustment instead of fixed speed steps for finer control. - Soft start function for longer fan life and reduced motor strain. - Timer range up to 999 minutes for long or short automatic runs. - Compact size 72 x 25 x 17 mm fits most desk setups and enclosures. Specifications - Model: ZK-UFS - Working voltage: DC 4 V to 12 V - Output voltage: DC 2.5 V to 8.0 V - Rated power: 5 W; do not overload the unit - Timer: 0 to 999 minutes - Operating temperature: -40 to 85 C - Operating humidity: 0% to 95% RH - Dimensions: 72 x 25 x 17 mm Important compatibility note - For non-adjustable USB fans that rely on an internal boost board, set the fan to its first gear before connecting to this governor. If the fan is left in second gear, the unit may not operate normally. How to use 1. Set the fan to first gear before connecting. 2. Plug the fan into the female USB socket on the governor. 3. Plug the male USB connector into your power source. 4. Turn the potentiometer knob left to increase output voltage and fan speed. 5. Turn the potentiometer knob right to decrease output voltage and fan speed. 6. Press the potentiometer once to enable or disable the output voltage. 7. Double click the potentiometer to turn the screen on or off. Any press will wake the display. 8. To set the timer, press and hold the potentiometer for about 3 seconds to enter timing set mode. Display shows dashes to disable the timer or numbers to enable timing. Use short presses to toggle the timing function. Turn left to increase minutes and right to decrease minutes. Press and hold about 3 seconds to save settings and begin countdown. Applications and use scenarios - Office desk cooling: Fine tune airflow and reduce noise while working on a laptop or desktop. - Bedroom or bedside fan: Use the timer and sleep mode to run a fan for a set time before automatic shutdown. - Electronics enclosure or chassis cooling: Provide controlled airflow for small equipment or workbench projects without overdriving fans. Included features summary - Stepless voltage governor for smooth speed adjustment. - Soft start for motor protection. - Timer function from 0 to 999 minutes. - Sleep mode and display on/off control. - Compact inline design for easy integration with USB-powered fans. This model provides reliable, adjustable control for a wide range of USB fans