Versatile compatibility This 3 pack USB fan speed controller set is designed to work with a wide range of 5V USB fans, including mini fans, desk fans, and air circulators. It provides airflow adjustment for any environment—whether you are working from home, in the office, or traveling. Precise speed adjustment Control your cooling experience with an intuitive dial. Output can be adjusted from DC 2.5V to 8V, allowing a gentle, whisper quiet breeze or maximum airflow to suit comfort and ambient temperature. Technical specifications Each compact controller measures 35 x 16.5 x 8.5 mm. Input voltage range is DC 4 12V, with a maximum rated power of 5W. The internal copper conductor provides low resistance and efficient, responsive performance. Simple installation No technical expertise required. Connect the controller between your USB power source and the fan for immediate use. The plug and play design makes it easy to start enjoying customised cooling within seconds of unboxing. What's included 3 compact USB fan speed controllers for flexible use with multiple fans or devices. Use case scenarios Home office: maintain a comfortable, quiet desk environment with precise airflow control. Travel or dorm room: compact, portable control that works with USB power banks and compact fans. Bedroom or study space: set different speeds for sleep, study, or relaxation without changing fans. Notes Optimized for 5V USB fans and compatible with a variety of small to medium fans. All specifications reflect the model's design for efficient, adjustable cooling.