Be Quiet! SILENT WINGS PRO 4 120/140mm PWM High-End Chassis Fan

be quiet. Optimized fan blades for the highest performance on radiators and heat sinks. Speed switch allows changing maximum PWM speed between medium-speed, high-speed and ultra-high-speed. Small tip clearance and a fan frame with a funnel-shaped air outlet for extremely high air pressure. Great noise-performance ratio at any RPM. 6-pole fan motor for less vibration and power consumption. Fluid-dynamic bearing enables very smooth operation. Individual and easy mounting systems for use as a case fan or with a radiator. Super-long life-span of up to 300,000h. Elegant look with high-grade fan sticker in an all-black design