Fractal Design Venturi HF-12 Black Case Fan FD-FAN-VENT-HF12-BK Featuring true FDB-bearings, providing silent operation coupled with a long lifespan Equipped with a counter-balancing magnet in the hub that reduces the axial tension on the bearing, further protecting the longevity of the bearing Comes with a low-speed adapter, for reducing the speed without the use of a fan controller Includes vibration-dampening corners, from solid high-quality synthetic rubber on the fans