Noctua NF-A15 PWM Cooling Fan - 5.51in Maximum Fan Diameter - 508.5 gal/min Maximum Airflow - 1200 rpm - SSO2 Bearing - 4-pin PWM

4-pin PWM connector enables quick and stable connection with cases Well designed blades and shroud let the air flow over a greater area to enable effective cooling SSO2 bearing combines the oil-based hydrodynamic bearings with an additional magnet to bring stabilization, precision, and durability