USB Fan Speed Controller with Stepless Control, Low Noise, Adjustable Airflow, 4-12V(Black)

USB Stepless Speed Controller for DC Fans Key benefits and why you need it: - Smooth, wide-range airflow control lets you set the fan from a gentle breeze to a powerful airflow for comfort or targeted cooling. - Low-noise operation reduces distraction in offices, bedrooms, or workspaces. - Compact mini design makes the controller easy to carry and integrate into portable setups. - Low power consumption and high operational efficiency extend runtime when used with battery packs or USB power sources. Main features: - Supports DC 4-12V input voltage to match various USB and battery-powered setups. - Outputs DC 2.5-7.5V with stepless voltage adjustment for fine control of fan speed. - Rated power 5W (do not overload). - Knob provides continuous speed adjustment; turn clockwise to increase speed and counterclockwise to decrease speed. The knob also functions as the power switch. - Compatible with standard USB fans. For non-adjustable USB fans that run on direct 5V, this controller allows variable output when connected within the specified range. - Works with two-speed USB fans that include an internal boost circuit board; when the fan is set to its second speed, the internal board increases the 5V supply before the motor to raise airflow. Performance and compatibility: - Input Voltage: DC 4-12V. - Output Voltage: DC 2.5-7.5V. - Rated Power: 5W (do not overload). - Designed for small USB-driven fans and portable ventilation needs, offering broad compatibility with common USB power sources and battery packs. Practical use scenarios: - Desk cooling: Fine-tune airflow from a personal USB fan at your workstation to reduce noise and maintain comfort during long work sessions. - Portable outdoor use: Connect to a USB power bank for adjustable cooling during travel, picnics, or outdoor events. - Electronics ventilation: Provide controlled airflow for small electronics, hobby projects, or custom enclosures where variable cooling is needed. Important notes and safe use: - When switching a two-speed fan to its second speed, first set the fan to single-speed mode; otherwise speed adjustment may fail. - Use the controller only within the specified input voltage range of DC 4-12V. - Do not exceed the rated power of 5W. Package contents: - Speed Controller x1. This controller provides precise, quiet, and portable speed control for USB fans while maintaining straightforward compatibility and simple operation.