XIGMATEK AOS (Aeronautical Oil System Bearing) XAF-F1451 140mm Case Fan Ultra Quiet Copper Bushing Axis Aeronautical Oil System Bearing Type: Case Fan Bearing Type: Aeronautical Oil System Bearing RPM: 800 - 1300 RPM Air Flow: 90.3 CFM (MAX) Noise Level: Power Connector: 4 pin with PWM Color: Black Compatibility: Case