Ultra-quiet UL-certified USB fan designed to cool various electronics and components. Features a multi-speed controller to set the fans speed to optimal noise and airflow levels. Dual-ball bearings have a lifespan of 67,000 hours and allows the fans to be laid flat or stand upright. USB plug can power the fan through USB ports found behind popular AV electronics and game consoles. Fan Size: 4.7 x 4.7 x 1 in. Airflow: 52 CFM Noise: 18 dBA Bearings: Dual Ball