The Pure Wings 2 family fans combine outstanding reliability, silent cooling, and a great price-for-performance ratio. It's impressive how much quiet technology the engineering team has crammed into these fans at this amazing price. They are the ultimate reason to put be quiet! silent cooling in your PC if you haven't already done so. The Pure Wings 2 PWM models combine all of the above essential features. They provide maximum cooling airflow and operating noise levels down to a silent. The increased air pressure makes the fans especially recommended for use in water cooling and air cooling setups.