Extreme airflow range for ultimate cooling and control 2 Ball Bearing designed for high speed high performance Better cooling and silent system performance thru PWM fan speed control 15 aerodynamic design fan blades for better airflow and stability 15 translucent blades Speed range from 500 to 2000 RPM with Excellent Airflow of up to 110 CFM 15 translucent Red blades design for ultimate airflow and low noise level at only 37 dBA