Legendary silence, epic performance and features
For the highest performance, optimized fan blades, especially for heat sinks designed radiator corners and a speed switch with 3 selectable speed options, Silent Wings Pro 4 140mm PWM is the most progressive, performant, and versatile fan by 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 (up to 2400 rpm)
• Small tip clearance and a fan frame with a funnel-shaped air outlet for extremely high air pressure
• Virtually inaudible operation at regular speed
• 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
• Valuable sleeved PWM cable and easy to install PWM connector
• Elegant look with high-grade fan sticker in an all-black design